The brutal murder of a construction site foreman looks like the work of a disgruntled employee, but forensic science points to an unlikely suspect.

A shooting victim mutters the name of her apparent assailant before dying, but fingerprint comparisons, handwriting analysis, ballistics and DNA testing show someone else close to home is the true killer.

A woman tells investigators that a man broke into her home wearing only underwear and gloves, killed her boyfriend, and raped and terrorized her.

After a Delaware man's mother is found dead, he tells a story that's so improbable police think it can't possibly be true.

A family vacation turns into a terrifying search for a missing wife and baby, then becomes a manhunt for a killer who committed a horrific crime.

A DNA dragnet catches a killer eight years after the kidnapping, rape and murder of a college coed in Oklahoma.

A nosy neighbor with a disturbing obsession becomes a suspect in a woman's murder at an upscale apartment complex; police discover an incredible link to an unrelated murder thousands of miles away.

A college student turns up dead and her boyfriend becomes a prime suspect when blood splatters are discovered on his wall.

Texas police hunt frantically for a brutal rapist. No one knows where he'll strike next, but given the increasingly violent nature of his crimes, he must be found soon.

After a young mother is found brutally murdered in her home, investigators find startling clues on her cell phone that could lead to her killer.

An amazing new forensic tool turns a cold case around.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Experts shed light on the shocking motive that prompted the Menendez brothers to murder their own parents, Jose and Kitty Menendez.

In a sensational, televised trial, Erik and Lyle Menendez were found guilty of murdering their parents; a shocking motive was behind the brothers' actions.

New theories emerge in the O.J. Simpson case, including a serial killer's confession, a possible hit man who claims responsibility for the murders.

New theories emerge in the O.J. Simpson case, including a serial killer's confession who may be a possible hit man who claims responsibility for the murders.

When detectives find a mismatched button in relation to a woman's death, they know they can follow the clue back to the killer.

A woman heads home after church, but never makes it there alive, triggering a homicide investigation.

Volunteers and police spend weeks searching for a missing girl. A psychic later leads them to a field where the body was found.

Forensic investigators try to stop a killer who is apparently responsible for two slayings in a community in South Carolina.

When DNA proves that a man who practically admits to a brutal attack is innocent, police wonder why he was willing to take the blame.

When a businessman is murdered, motives and suspects are plentiful. Was it simply a disgruntled employee or client? Or do some racy photos hold the clue to the crime?

A family break turns into a nightmare when the wife is found face-down in a lake. With no idea whether it was murder, an accident or suicide, police turn to a new forensic technique.

When friends see a woman in the back of a car flailing her arms and screaming, they assume she is having fun, but when they later come upon a jacket and a pool of blood, they realize they witnessed an abduction in progress.

An attack on a couple's home leaves the husband dead, the wife gravely injured and their son as a prime suspect; hundreds of miles away, a DNA sample may lead to the killer.

Detectives think they've solved a murder when they find the weapon and victim's blood in a man's flat, but the evidence may have been planted.

Detectives search for the bombers of two churches in Illinois, hoping that the materials used in the remnants of the handmade bombs will offer the clues to catch the culprits.

There was no apparent reason for the young, healthy college student to be dead; but when the medical examiner found the tiniest of clues during the autopsy, investigators were able to unravel the mystery of betrayal and revenge.

A woman is stabbed a hundred times and her body positioned in a suggestive manner. This could be a hate crime against women.

Police are able to create a composite sketch of a man burnt beyond recognition. But tracking the killer is more challenging.

By cutting a strand of a murdered man's hair into sections, forensics reveal a record of his last six months alive, and find he was frequently ingesting huge amounts of arsenic.

A bullet-riddled car, a missing driver, and no witnesses, an ambush or a random attack; the clue was something so tiny, it was measured in millionths of a meter.

Teenager is found half-naked with her throat slit; a single foreign hair found on her thumb may finger the killer.

Two women who lived in the same apartment complex were brutally murdered; the similarities of the crime scenes led police to believe they were dealing with a serial killer who hated women, and they had to find him before he struck again.

When DNA proves that a man who practically admits to a brutal attack is innocent, police wonder why he was willing to take the blame.

When a businessman is murdered, motives and suspects are plentiful. Was it simply a disgruntled employee or client? Or do some racy photos hold the clue to the crime?

A family break turns into a nightmare when the wife is found face-down in a lake. With no idea whether it was murder, an accident or suicide, police turn to a new forensic technique.

When friends see a woman in the back of a car flailing her arms and screaming, they assume she is having fun, but when they later come upon a jacket and a pool of blood, they realize they witnessed an abduction in progress.

An attack on a couple's home leaves the husband dead, the wife gravely injured and their son as a prime suspect; hundreds of miles away, a DNA sample may lead to the killer.

Detectives think they've solved a murder when they find the weapon and victim's blood in a man's flat, but the evidence may have been planted.

Detectives search for the bombers of two churches in Illinois, hoping that the materials used in the remnants of the handmade bombs will offer the clues to catch the culprits.

There was no apparent reason for the young, healthy college student to be dead; but when the medical examiner found the tiniest of clues during the autopsy, investigators were able to unravel the mystery of betrayal and revenge.

A woman is stabbed a hundred times and her body positioned in a suggestive manner. This could be a hate crime against women.

Police are able to create a composite sketch of a man burnt beyond recognition. But tracking the killer is more challenging.

By cutting a strand of a murdered man's hair into sections, forensics reveal a record of his last six months alive, and find he was frequently ingesting huge amounts of arsenic.

A bullet-riddled car, a missing driver, and no witnesses, an ambush or a random attack; the clue was something so tiny, it was measured in millionths of a meter.

Teenager is found half-naked with her throat slit; a single foreign hair found on her thumb may finger the killer.

Two women who lived in the same apartment complex were brutally murdered; the similarities of the crime scenes led police to believe they were dealing with a serial killer who hated women, and they had to find him before he struck again.

A gruesome find in a small town church sends investigators searching for a killer.

An insurance agent is shot execution style in his office, but the killer leaves no fingerprints, and there are no murder weapon found at the scene; then investigators discover a critical clue invisible to the naked eye that cracks the case.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

A healthy, young mother mysteriously dies after a minor traffic accident triggering an investigation.

Investigators search for clues after a body is discovered in a watery grave.

The murder of teacher's aide leaves a hole in the heart of her small community; as rumors spread about suspects, the actual perpetrator slips further away.

Father and teacher are found hanging naked from a tree with the letters F-E-D on his chest; with barely any evidence to work with, investigators turn to these letters for answers.

A single mom vanishes without a trace; foul play is confirmed after a truck toolbox opens with her body inside; homicide detectives investigate men she matched on dating sites, men from work, and a lover with a violent past.

A 20-year-old woman sets out on her bike and never returns; her body is found a few miles from her house with a gunshot wound to the head; years go by without any evidence or leads, until new investigators and technology breaks the case.

A navy lieutenant is murdered while deployed out to sea; arsenic poisoning is the cause of death; investigators discover he had more than his fair share of enemies, but it takes years before investigators discover what really happened to him.

A building manager finds the lifeless body of a young woman in the bathtub; when questioned, an ex-con living downstairs lies to police; the lies do not prove murder and the case goes cold, then a new forensic tool examines the evidence.

Weeks after a student vanishes, the body of an unknown female is found in the ashes of a fire 700 miles away; an alert policeman realizes the crimes could be connected.

Investigators face a growing list of suspects after a beautiful flight attendant is brutally murdered in her own home.

The assistant manager of the restaurant had been stabbed to death; police knew why he'd been killed: $8,000 was missing from the safe. As to who was responsible, his family and friends couldn't even imagine who'd want to hurt him.

Florida authorities rely on DNA evidence to try to nail the killer of a woman who was abducted from her late-night job at a convenience store, raped and strangled.

A wild fire in a secluded parking lot leads police to discover a dreadful homicide, with the suspect's image caught by security cameras.

After a prominent Arizona surgeon is found stabbed to death outside his office, investigators uncover an unlikely suspect with deep pockets and an even deeper hatred for the doctor.

Police don't have a basis for comparison to match shoe impressions, blood drops and DNA evidence from a murder scene.

A masked gunman kills two members of a family and wounds two others after they interrupt his burglary at their upscale suburban home.

A killer leaves equally incriminating evidence at the scene when he meticulously wipes away his fingerprint and shoe impressions.

After a woman is found dead at a yacht club in California in an apparent case of love gone wrong, investigators discover her home life was as dramatic as films made in nearby Hollywood.

The brutal murder of a state park employee over $2,000 rattles her co-workers and tourists while leaving police to sift through hundreds of leads.

When evidence shows a woman's rape and murder, police must find the killer as well as the victim.

A week after a couple disappears from the beach, police get a mysterious lead from a robbery.

Fifteen years later, DNA technology leads to justice for a murdered woman and her savagely beaten 4-year-old daughter.

A quiet waitress who hasn't been to work in two days vanishes without a trace; police suspect a date gone wrong.

The search for a missing exotic dancer led police to an isolated 75-acre site where someone had been shot and cremated, thus destroying all evidence... almost; piece of a foot provided enough DNA for a genetic profile and positive ID.

After years of suffering domestic abuse, a young woman is found murdered in her bathtub; among numerous clues, a hamburger bun proves the most incriminating.

Evidence that includes threatening emails, a missing person and an abandoned truck lead police to a woman's suspected killer, but they don't have the victim's body.

A wild fire in a secluded parking lot leads police to discover a dreadful homicide, with the suspect's image caught by security cameras.

After a prominent Arizona surgeon is found stabbed to death outside his office, investigators uncover an unlikely suspect with deep pockets and an even deeper hatred for the doctor.

Police don't have a basis for comparison to match shoe impressions, blood drops and DNA evidence from a murder scene.

A masked gunman kills two members of a family and wounds two others after they interrupt his burglary at their upscale suburban home.

A killer leaves equally incriminating evidence at the scene when he meticulously wipes away his fingerprint and shoe impressions.

After a woman is found dead at a yacht club in California in an apparent case of love gone wrong, investigators discover her home life was as dramatic as films made in nearby Hollywood.

The brutal murder of a state park employee over $2,000 rattles her co-workers and tourists while leaving police to sift through hundreds of leads.

When evidence shows a woman's rape and murder, police must find the killer as well as the victim.

A week after a couple disappears from the beach, police get a mysterious lead from a robbery.

Fifteen years later, DNA technology leads to justice for a murdered woman and her savagely beaten 4-year-old daughter.

A quiet waitress who hasn't been to work in two days vanishes without a trace; police suspect a date gone wrong.

The search for a missing exotic dancer led police to an isolated 75-acre site where someone had been shot and cremated, thus destroying all evidence... almost; piece of a foot provided enough DNA for a genetic profile and positive ID.

After years of suffering domestic abuse, a young woman is found murdered in her bathtub; among numerous clues, a hamburger bun proves the most incriminating.

Evidence that includes threatening emails, a missing person and an abandoned truck lead police to a woman's suspected killer, but they don't have the victim's body.

Stories from across the world and refreshing conversations with Audie Cornish.

Stories from across the world and refreshing conversations with Audie Cornish.

In Northern California, a masked predator meticulously plans his sexual assaults by studying the habits and routines of his female prey; after 27 years on the loose, police close in on the man they believe to be the NorCal Rapist.

In Northern California, a masked predator meticulously plans his sexual assaults by studying the habits and routines of his female prey; after 27 years on the loose, police close in on the man they believe to be the NorCal Rapist.

A look at the deal makers and hangers-on who attached themselves to Aileen Wuornos, who is known as America's first female serial killer.

A look at the deal makers and hangers-on who attached themselves to Aileen Wuornos, who is known as America's first female serial killer.

The Zodiac Killer terrorizes Northern California in the late 1960s; he taunts the public with cryptic clues, threats of violence and ciphers that are supposed to lead to his identity, but mostly go nowhere.

The Zodiac Killer terrorizes Northern California in the late 1960s; he taunts the public with cryptic clues, threats of violence and ciphers that are supposed to lead to his identity, but mostly go nowhere.

A woman has an accidental fall down a flight of stairs and appears to have hit her head, but the lack of blood splatter and misplaced shoes lead police to believe the fall was staged.

A church member gets gunned down after leaving choir practice; although witnesses see little and not much evidence exists, investigators learn that she had been having affairs for years.

When a man perishes in a fire while working in his garage, his death is initially ruled an accident until a forensic odontologist changes the direction of the case.

Lack of evidence compels investigators to look beyond the obvious when a woman is beaten to death at her in-laws house.

A man is found dead of an apparent suicide. But soon after, information emerges which reveals a much more menacing scenario.

A dismembered body is dumped on the side of the New Jersey Turnpike and before police realize it, bodies are turning up between two states.

A young bride-to-be is gunned down in her own home. The attack is personal and as investigators start digging, they uncover the man she loved was living a lie.

Tara Munsey went missing after a work shift at a Virginia restaurant and it is unknown if she ran away or if she was the victim of foul play.

An Ohio woman and her two daughters go missing while vacationing in Florida; their corpeses are found floating in Tampa Bay with a hand-written note by one of the victims; putting it on five billboards helps them find the killer.

Four young adults are murdered in an affluent Texas neighborhood, with little evidence but two people walking by dressed in black.

A young college student is found dead in her apartment and the autopsy rules the death a homicide by an unknown male suspect.

The killer removed the computer that links him to the murder of a woman and her soon-to-be ex-husband that he had met online.

A community is shocked when police discover a woman raped and murdered in broad daylight on a public trail.

A real estate developer is shot and his wife becomes the prime suspect, until the bullet is linked to a weapon reported missing 20 years ago.

A body is found stuffed into a suitcase forcing the police to search though the landfill for another missing victim.

A woman goes missing for a month with the only clues being a set of keys, a fingerprint and a code.

Police discover a mask near the crime scene and hope that it leads to the killer of a funeral director.

A killer assaults a young mother in her home, but despite meticulous washing of the crime scene, a single hair remains to lead authorities to the culprit.

A man is found dead of an apparent suicide. But soon after, information emerges which reveals a much more menacing scenario.

A dismembered body is dumped on the side of the New Jersey Turnpike and before police realize it, bodies are turning up between two states.

A young bride-to-be is gunned down in her own home. The attack is personal and as investigators start digging, they uncover the man she loved was living a lie.

Tara Munsey went missing after a work shift at a Virginia restaurant and it is unknown if she ran away or if she was the victim of foul play.

An Ohio woman and her two daughters go missing while vacationing in Florida; their corpeses are found floating in Tampa Bay with a hand-written note by one of the victims; putting it on five billboards helps them find the killer.

Four young adults are murdered in an affluent Texas neighborhood, with little evidence but two people walking by dressed in black.

A young college student is found dead in her apartment and the autopsy rules the death a homicide by an unknown male suspect.

The killer removed the computer that links him to the murder of a woman and her soon-to-be ex-husband that he had met online.

A community is shocked when police discover a woman raped and murdered in broad daylight on a public trail.

A real estate developer is shot and his wife becomes the prime suspect, until the bullet is linked to a weapon reported missing 20 years ago.

A body is found stuffed into a suitcase forcing the police to search though the landfill for another missing victim.

A woman goes missing for a month with the only clues being a set of keys, a fingerprint and a code.

Police discover a mask near the crime scene and hope that it leads to the killer of a funeral director.

A killer assaults a young mother in her home, but despite meticulous washing of the crime scene, a single hair remains to lead authorities to the culprit.

Stories from across the world and refreshing conversations with Audie Cornish.

Stories from across the world and refreshing conversations with Audie Cornish.

Melanie Zanona; Catherine Lucey; Isaac Arnsdorf.

Mother of two Crystal McDowell vanishes as Hurricane Harvey rocks Houston; surveillance video leads investigators to her twisted killer.

Former model, Samira Frasch, was living a life of extravagance until tragedy struck; the mother of two is found dead at the bottom of her swimming pool and both her children are missing from the home.

Aspiring cosmetologist Shannon Graves is found dismembered inside a padlocked freezer but when another woman is spotted driving her car and going into her apartment, detectives discover a chilling cover-up.

Successful doctor and mom of two, Teresa Sievers, is found bludgeoned to death in her kitchen after returning home from a family vacation.

A 41-year-old mother of three was brutally stabbed nearly 200 times in front of her two youngest children; investigators reveal a sick and twisted motive behind the deadly rampage, and her daughter who witnessed the attack speaks for the first time.

The investigation into the disappearance of flight attendant Helle Crafts leads to the murder conviction of her pilot husband.

Scientists and detectives use DNA to solve a string of rapes and murders.

Police believe they have a serial rapist and murderer, but DNA testing and research leads to another arrest and conviction.

In 1976, 182 war veterans in Philadelphia become hospitalized with pneumonia-like symptoms and 29 die; the disease resurfaces every few years.

After a wealthy Southern physician gets murdered with a baseball bat, his wife and a handyman become convicted of the crime.

In 1971, John List disappears after murdering his mother, wife and three children; he eludes the law for years until an age-scaled sculpture of the suspect and a true-crime TV program helps lead to his arrest in 1989.

An 11-year-old boy comes down with a fever and diarrhea after eating an undercooked burger; when his condition worsens, his mother drives him to a hospital and doctors discover E. coli destroying his body.

Florida police search for a serial rapist and murderer who left small red fibers on each of his 10 victims.

When an English couple go missing, police suspect their son killed them and must rely on mud and blood samples found in the couple's two cars to find their bodies.

Experts attempt to discover the source of heavy fog on Highway I-75 in Tennessee, which caused a 99-car accident and 12 deaths.

When a woman goes missing from her home, police focus on her husband when an airline luggage tag and luminol point to an affair and murder; footage from a TV crew and Coast Guard photographs lead investigators to the suspect's missing boat.

When a woman exhibits strange flu-like symptoms before dying, investigators discover someone added thallium to her soda; detectives initially suspect her husband, but the case takes a sinister turn.

When dozens of infants develop serious breathing problems in the Cleveland area, doctors and investigators search high and low for the cause.

A well-liked bank vice president collapses and dies after taking pain pills laced with cyanide; the search for a motive reveals a callous suspect who had murdered once before.

Evidence reveals a teacher who complained of being stalked and harassed by another teacher was scamming police.

A man kills two people with bombs in an effort to get investors off his back, but authorities catch onto him and he becomes sentenced to life with no chance of parole.

A man arrested for the sexual assault and attempted murder of a boy in a European country becomes linked to a murder in Zurich, Switzerland, through analysis of microorganisms.

Heavy rains and snow run-off carry manure into Milwaukee's water supply in 1993, leading to an epidemic of gastrointestinal illness affecting 400,000 people.

After a wealthy Southern physician gets murdered with a baseball bat, his wife and a handyman become convicted of the crime.

In 1971, John List disappears after murdering his mother, wife and three children; he eludes the law for years until an age-scaled sculpture of the suspect and a true-crime TV program helps lead to his arrest in 1989.

An 11-year-old boy comes down with a fever and diarrhea after eating an undercooked burger; when his condition worsens, his mother drives him to a hospital and doctors discover E. coli destroying his body.

Florida police search for a serial rapist and murderer who left small red fibers on each of his 10 victims.

When an English couple go missing, police suspect their son killed them and must rely on mud and blood samples found in the couple's two cars to find their bodies.

Experts attempt to discover the source of heavy fog on Highway I-75 in Tennessee, which caused a 99-car accident and 12 deaths.

When a woman goes missing from her home, police focus on her husband when an airline luggage tag and luminol point to an affair and murder; footage from a TV crew and Coast Guard photographs lead investigators to the suspect's missing boat.

When a woman exhibits strange flu-like symptoms before dying, investigators discover someone added thallium to her soda; detectives initially suspect her husband, but the case takes a sinister turn.

When dozens of infants develop serious breathing problems in the Cleveland area, doctors and investigators search high and low for the cause.

A well-liked bank vice president collapses and dies after taking pain pills laced with cyanide; the search for a motive reveals a callous suspect who had murdered once before.

Evidence reveals a teacher who complained of being stalked and harassed by another teacher was scamming police.

A man kills two people with bombs in an effort to get investors off his back, but authorities catch onto him and he becomes sentenced to life with no chance of parole.

A man arrested for the sexual assault and attempted murder of a boy in a European country becomes linked to a murder in Zurich, Switzerland, through analysis of microorganisms.

Heavy rains and snow run-off carry manure into Milwaukee's water supply in 1993, leading to an epidemic of gastrointestinal illness affecting 400,000 people.

A murder victim's final moments are caught on tape; the crime scene looks like a clear robbery-murder; text evidence at first points to a jilted lover, but police identify a second suspect with a motive.

A wounded woman calls 911; her husband, who wants a divorce, gets a hard look from police, but he has an airtight alibi during the murder; forensic science of ballistics draws a direct connection.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

More than 900 Americans died in an isolated jungle in northern Guyana in November 1978; Jim Jones has gone down in history as a madman who drove his followers to suicide, but the truth is more complicated and tragic than that.

More than 900 Americans died in an isolated jungle in northern Guyana in November 1978; Jim Jones has gone down in history as a madman who drove his followers to suicide, but the truth is more complicated and tragic than that.

From 1976 to 1977, David Berkowitz terrorizes New York City under his creepy self-given moniker: the "Son of Sam"; he is among the most infamous serial killers in American history.

In 1977, the city of New York is stalked by a seemingly faceless serial killer known as "Son of Sam"; after his final shooting takes him to Brooklyn, a twist of fate and a little luck leads to his capture.

Autopsies reveal that a string of unexplained deaths in Omaha resulted from poison-induced liver disintegration.

In a series of murders near Sacramento, Calif., a killer gags and molests prostitutes, cuts their clothes in random patterns and cuts off their hair; microscopic evidence helps solve the case.

After the discovery of a skull in the forest near a boy scout camp, police use facial reconstruction to identify the body.

Investigators use obscure evidence to find the person responsible for killing justice officials with mail bombs in the South.

Forensic scientists provide authorities with evidence that a death deemed accidental 20 years ago was actually murder.

Detectives learn that a genetic disorder caused the deaths of a woman's children, resulting in an overturned conviction.

When a young woman goes missing on the way to the train station, investigators use a strand of hair and a bloody pillowcase to find a suspect.

Investigators reopen a case from 1984 involving the rape of a young Virginia woman when DNA testing refutes her identification of the rapist and calls everything into question, leading to the accused person's exoneration.

A speck of bicycle paint and a speck of nickel left over from a collision with a twice-convicted child molester's car provide critical clues in the murder of a 9-year-old.

A 2-year-old boy's brain seizures and breathing problems baffle doctors until they learn the mother exhibits signs of Munchausen syndrome by proxy, a rare condition that led her to physically abuse her son and contributed to her daughter's death.

Two years after an 18-year-old's murder in Albion, Mich., a tiny drop of blood and burned bones lead police to her killers.

A mother claims that an intruder murdered her two sons, but lacking a motive, police use blood-spatter analysis and behavioral profiling to reconstruct a different scenario.

A routine missing persons report leads Texas police to discover a deadly love triangle; evidence found in a suspect's home matches the murder scene and leads to the indictment of the victim's girlfriend and her lover.

A 1995 fire razes the mansion of a Kansas doctor, killing two of her three children; disturbing accounts from an ex-husband lead investigators to believe the doctor set the blaze herself.

A husband confesses to his wife's murder, only to be found not guilty a year later when a phone tip and forensic evidence point to another.

In Lorton, Va., police attempt to determine who abducted 5-year-old Melissa Brannen after she disappears from a Christmas party, but cannot be certain until they match hair from a rabbit-fur jacket Brannen wore that day.

When a Pennsylvania man checks into a hospital for leg pain and later dies of thallium poisoning, police investigate his wife and find her in the process of collecting an insurance payment for her previous husband's death.

Police exhume the body of Karla Brown, murdered in her home in 1978, to study bite wounds, which eventually lead to the killer.

Forensic scientists provide authorities with evidence that a death deemed accidental 20 years ago was actually murder.

Detectives learn that a genetic disorder caused the deaths of a woman's children, resulting in an overturned conviction.

When a young woman goes missing on the way to the train station, investigators use a strand of hair and a bloody pillowcase to find a suspect.

Investigators reopen a case from 1984 involving the rape of a young Virginia woman when DNA testing refutes her identification of the rapist and calls everything into question, leading to the accused person's exoneration.

A speck of bicycle paint and a speck of nickel left over from a collision with a twice-convicted child molester's car provide critical clues in the murder of a 9-year-old.

A 2-year-old boy's brain seizures and breathing problems baffle doctors until they learn the mother exhibits signs of Munchausen syndrome by proxy, a rare condition that led her to physically abuse her son and contributed to her daughter's death.

Two years after an 18-year-old's murder in Albion, Mich., a tiny drop of blood and burned bones lead police to her killers.

A mother claims that an intruder murdered her two sons, but lacking a motive, police use blood-spatter analysis and behavioral profiling to reconstruct a different scenario.

A routine missing persons report leads Texas police to discover a deadly love triangle; evidence found in a suspect's home matches the murder scene and leads to the indictment of the victim's girlfriend and her lover.

A 1995 fire razes the mansion of a Kansas doctor, killing two of her three children; disturbing accounts from an ex-husband lead investigators to believe the doctor set the blaze herself.

A husband confesses to his wife's murder, only to be found not guilty a year later when a phone tip and forensic evidence point to another.

In Lorton, Va., police attempt to determine who abducted 5-year-old Melissa Brannen after she disappears from a Christmas party, but cannot be certain until they match hair from a rabbit-fur jacket Brannen wore that day.

When a Pennsylvania man checks into a hospital for leg pain and later dies of thallium poisoning, police investigate his wife and find her in the process of collecting an insurance payment for her previous husband's death.

Police exhume the body of Karla Brown, murdered in her home in 1978, to study bite wounds, which eventually lead to the killer.

A religious woman is shot execution style in the suburbs of Michigan; surveillance video reveals it was a trio of killers; eventually, detectives get a break: a handwritten note.

Three sex workers are murdered and left along a river; a serial killer was on the loose and for years the perp was never identified.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Uncovering how Anna Nicole Smith's lavish lifestyle may have contributed to her mysterious death.

Revelations of what Michael Jackson's children and staff witnessed prior to his death and an investigation into the claims that Jackson took his own life.

Revelations of what Michael Jackson's children and staff witnessed prior to his death and an investigation into the claims that Jackson took his own life.

New details emerge surrounding singer Whitney Houston's last days and her tumultuous relationship with Bobby Brown.

A new life-insurance policy sparks suspicions of murder when a Nova Scotia schoolteacher's body is found at the bottom of her basement stairs.

A beverage company pleads guilty to violating federal safety laws when a baby dies from E. coli after drinking apple juice.

A woman who survived a deadly childhood fire sends police a letter charging that her father killed her mother 30 years ago.

After more than 20 people on a Native American reservation die suddenly from a flu-like disease, Navajo medicine men provide a clue that leads to a most unlikely killer.

While at a real estate conference in St. Louis, a man finds his wife drowned in the bathtub in their hotel room.

A cunning serial rapist who leaves no decisive evidence forces investigators to rely on geographical profiling in their search for an identity; DNA from a cigarette butt may provide the final piece of evidence needed to catch the suspect.

New evidence including fibers and weather patterns point to a different killer in the 1986 case of a Pennsylvania dentist's murdered wife.

Insects and a single strand of hair uncover an additional suspect in the killing of a young mother and her baby in Lehigh Valley, Pa.

A decomposed body is found in a barrel, and a dilapidated address book may hold the answer, but investigators must find a way to read the pages because the passage of 30 years has turned them blank.

When a policeman's home burns to the ground, he later arrests a man who confesses to arson, but the confession seems dubious.

A woman identifies her husband as her attacker, but questions arise 16 years later regarding her recollections.

A young girl is found dead, the victim of an apparent sex killer; there are few clues to the killer's identity, but authorities are intrigued by unusual orange fibers embedded in clothing found near the victim.

Police charge Alan "The Zenith Man" Ridley with murdering his wife, Virginia, but following an autopsy, medical detectives believe he may not have killed his wife after all.

With children dying at an alarming rate at a Texas hospital, authorities narrow down their probe to one nurse, but the murder weapon remains elusive.

When the decomposed body of a young girl is discovered, police have no clues to her identity, but days earlier, a stabbing victim told them she thought she might have witnessed a murder.

When a doctor's wife disappears, investigators use concrete from the doctor's yard and the recollections of a child to determine what happened.

Romanian archbishop Valerian D. Trifa, living in the U.S., is accused of being a Nazi war criminal, and forensic experts find evidence on an incriminating, 40-year-old postcard.

Investigators look into the shooting death of Russ Stager, a popular gym teacher, and discover that his death was not an accident; a message the victim recorded before his death reveals a story of greed.

While at a real estate conference in St. Louis, a man finds his wife drowned in the bathtub in their hotel room.

A cunning serial rapist who leaves no decisive evidence forces investigators to rely on geographical profiling in their search for an identity; DNA from a cigarette butt may provide the final piece of evidence needed to catch the suspect.

New evidence including fibers and weather patterns point to a different killer in the 1986 case of a Pennsylvania dentist's murdered wife.

Insects and a single strand of hair uncover an additional suspect in the killing of a young mother and her baby in Lehigh Valley, Pa.

A decomposed body is found in a barrel, and a dilapidated address book may hold the answer, but investigators must find a way to read the pages because the passage of 30 years has turned them blank.

When a policeman's home burns to the ground, he later arrests a man who confesses to arson, but the confession seems dubious.

A woman identifies her husband as her attacker, but questions arise 16 years later regarding her recollections.

A young girl is found dead, the victim of an apparent sex killer; there are few clues to the killer's identity, but authorities are intrigued by unusual orange fibers embedded in clothing found near the victim.

Police charge Alan "The Zenith Man" Ridley with murdering his wife, Virginia, but following an autopsy, medical detectives believe he may not have killed his wife after all.

With children dying at an alarming rate at a Texas hospital, authorities narrow down their probe to one nurse, but the murder weapon remains elusive.

When the decomposed body of a young girl is discovered, police have no clues to her identity, but days earlier, a stabbing victim told them she thought she might have witnessed a murder.

When a doctor's wife disappears, investigators use concrete from the doctor's yard and the recollections of a child to determine what happened.

Romanian archbishop Valerian D. Trifa, living in the U.S., is accused of being a Nazi war criminal, and forensic experts find evidence on an incriminating, 40-year-old postcard.

Investigators look into the shooting death of Russ Stager, a popular gym teacher, and discover that his death was not an accident; a message the victim recorded before his death reveals a story of greed.

He is a sex offender and a murderer who attacks in a terrifying rage; this predator manages to evade capture for years, but he leaves evidence behind, his palm print; detectives are determined to put a face to the print.

When a house fire kills the only doctor in a small town, an arson investigation leads to the son of the doctor's nurse; the prosecutor worries this might have been a miscarriage of justice.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Todd Kohlhepp's double life is exposed after police rescue a young woman chained like a dog inside a shipping container on his property.

A registered sex offender lures Cherish Perrywinkle, 8, away from a Walmart, and that's just the beginning of a night of terror, all caught on camera.

Fitness instructor Missy Bevers is stabbed and bludgeoned to death while setting up for an early-morning workout class at the local church; surveillance cameras capture a series of images of her killer lurking in the hallways.

Model Tara Lambert hires a hit man to kill her husband's ex-wife and put her in a wood chipper, but she doesn't know that cameras are rolling.

A money launderer is found dead in the ocean and the only obvious clues to his identity are a Rolex watch and a tattoo; the anchor with which he is weighed down proves most helpful in solving the crime.

The apparent suicide of Dr. Darryl Sutorius, a respected heart surgeon, is questioned when an investigation reveals his new wife's violent history.

The 1992 hit-and-run death of 6-year-old Nicole Rae Walker leads to a groundbreaking trial as experts submit a video reconstruction of the incident, implicating a drunk driver and demonstrating the viability of video testimony.

Specialists including a NASA vendor help police reconstruct a damaged surveillance video to catch the murderer of convenience store employee Wanda Mason in Lansing, Mich.

When a young woman goes missing, the police investigation reveals that she led a double life - student by day, call girl by night - but when her body is discovered, even more strange truths are uncovered.

A tiny clue inside a suspect's watchband and a popular television show help solve the case of a woman's disappearance.

One year after Maine resident Pearl A. Bruns' disappearance, forensic technology helps to find her body and determine who was responsible for her death.

When 4-year-old April Renee Tucker is found dead in her backyard, her parents tell the police that neighborhood dogs attacked and killed her, but the injuries on her body don't match their account of what happened.

San Diego police investigate the murder of a missing person whose hands turn up in a dumpster; an anonymous letter, containing details only the killer would know, offers clues to solving the case.

One year after her father's death, a teen's role in a high school production of "Hamlet" causes her to reveal the chilling truth behind her family's tragedy.

A mother puts her hope in the internet and an independent investigation to clear her name after authorities charge her with murdering her 17-month-old son in a fire considered to be intentionally set.

A forensic scientist uses his skills to preserve a footprint left in snow to help authorities nab two men suspected of robbing an Ontario couple and shooting the husband in the head.

Fingerprints taken from a piece of cloth help solve the rape and murder of a 22-year-old woman in Henrico County, Va.

The FBI profiles a suspect in the kidnapping and murder of a 6-year-old girl during an evening church service; a witness leads authorities to the likely killer, but then becomes a victim herself.

Photographs found in a dumpster lead to the killer of Los Angeles model Linda Sobek; the man claims he did not intentionally kill her despite evidence to the contrary.

A murder mystery theater performance in Easton, Md., turns into a real-life mystery when a body is found after the performance ends.

When a woman dies in a horseback riding accident, police uncover a web of lies in her husband's background after his suspicious behavior prompts a closer look.

A serial killer in Tampa, Fla., taunts police by strangling prostitutes and leaving their bodies in plain sight, but tire marks and fibers lead to the culprit.

When a young woman goes missing, the police investigation reveals that she led a double life - student by day, call girl by night - but when her body is discovered, even more strange truths are uncovered.

A tiny clue inside a suspect's watchband and a popular television show help solve the case of a woman's disappearance.

One year after Maine resident Pearl A. Bruns' disappearance, forensic technology helps to find her body and determine who was responsible for her death.

When 4-year-old April Renee Tucker is found dead in her backyard, her parents tell the police that neighborhood dogs attacked and killed her, but the injuries on her body don't match their account of what happened.

San Diego police investigate the murder of a missing person whose hands turn up in a dumpster; an anonymous letter, containing details only the killer would know, offers clues to solving the case.

One year after her father's death, a teen's role in a high school production of "Hamlet" causes her to reveal the chilling truth behind her family's tragedy.

A mother puts her hope in the internet and an independent investigation to clear her name after authorities charge her with murdering her 17-month-old son in a fire considered to be intentionally set.

A forensic scientist uses his skills to preserve a footprint left in snow to help authorities nab two men suspected of robbing an Ontario couple and shooting the husband in the head.

Fingerprints taken from a piece of cloth help solve the rape and murder of a 22-year-old woman in Henrico County, Va.

The FBI profiles a suspect in the kidnapping and murder of a 6-year-old girl during an evening church service; a witness leads authorities to the likely killer, but then becomes a victim herself.

Photographs found in a dumpster lead to the killer of Los Angeles model Linda Sobek; the man claims he did not intentionally kill her despite evidence to the contrary.

A murder mystery theater performance in Easton, Md., turns into a real-life mystery when a body is found after the performance ends.

When a woman dies in a horseback riding accident, police uncover a web of lies in her husband's background after his suspicious behavior prompts a closer look.

A serial killer in Tampa, Fla., taunts police by strangling prostitutes and leaving their bodies in plain sight, but tire marks and fibers lead to the culprit.

A young woman is found murdered on the side of a rural driveway; the victim had been out with friends; the investigation would remain unsolved; until three decades later, when forensics from an unrelated crime helps break the case.

A hearing impaired 77-year-old on a road trip is shot to death because the man cannot hear his assailant's demands; random murders are among the hardest crimes to solve, but investigators are determined to bring this case to justice.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Investigating a wide range of suspects and evidence in the killing of JonBenet Ramsey.

Investigating a wide range of suspects and evidence in the killing of JonBenet Ramsey.

Examining the factors that led to the crash that killed John F. Kennedy Jr. and a never before seen interview with a person who may have been the last person to speak to JFK Jr, moments before the crash.

Examining the factors that led to the crash that killed John F. Kennedy Jr. and a never before seen interview with a person who may have been the last person to speak to JFK Jr, moments before the crash.

Missouri police are thrust into a bizarre web of homeless drifters and cattle auctions when they are called to retrieve a dead body.

A killer wants to outwit the police and keep the identity of his victim secret so he removes the teeth; however, lab tests on the skull reveal not just the horrific nature of the murder, but the identity of the victim too.

When a fundamentalist group is accused of robbing banks, authorities know they are dealing with experienced criminals and overwhelming evidence, but the defense is very well-funded.

When a young doctor is accused of sedating and sexually assaulting two of his female patients, DNA tests show him to be innocent, but the women persist with their claims; seven years later, a private investigation leads to a surprising discovery.

The search for the killer of two teenagers in Texas shows a behavioral study on how most serial killers also have a history of abusing animals.

When a farmer's wife disappears, the tests of a plant pathologist and a dendrochronologist lead to a surprising revelation.

A son who is convinced of his mother's innocence in the death of his father enrolls in law school to try and clear her name.

Despite a patient's claim that the cut to his hand had been caused by a dumpster, the doctor treating the injury recognizes it as something else - and soon becomes the chief witness in a murder case.

The pornography empire cultivated by brothers Artie and Jim Mitchell crumbles when one turns up dead and his brother confesses to shooting him; investigators question whether the shooting was premeditated.

When prison guard Donna Payant's body is discovered at a landfill, a medical examiner uses a "signature" clue to link her death to a murder the same examiner investigated 10 years earlier.

When a 9-year-old girl vanishes on her way to school, the entire community helps with the search; detectives believe her mother may be involved, and a hidden fingerprint seals the case.

The investigation of a murder case in New Jersey is stalled until a similar attack occurs on a state trooper in Maine.

A young woman goes missing without leaving many clues, but the advanced technology on offer makes it possible for cat hairs and insects to help build an image of the abductor.

Blood spatter analysis and an investigation lead police to the truth when a pregnant woman is found dead in her home.

A mother is determined to discover what happened when her daughter is injured in a hit-and-run accident.

Forensic science and deductive reasoning determine what happened to a mother and daughter while they were on a shopping spree.

Exploring how an American hit single from 1966 - "The Cheater" by Bob Kuban and the In-Men - foreshadowed the demise of the group's lead singer, Walter Scott.

Eight years after a man confessed to the murder of a young woman, another man claims that he committed the crime, and investigators must use forensic evidence to determine the true killer.

The search for the killer of two teenagers in Texas shows a behavioral study on how most serial killers also have a history of abusing animals.

When a farmer's wife disappears, the tests of a plant pathologist and a dendrochronologist lead to a surprising revelation.

A son who is convinced of his mother's innocence in the death of his father enrolls in law school to try and clear her name.

Despite a patient's claim that the cut to his hand had been caused by a dumpster, the doctor treating the injury recognizes it as something else - and soon becomes the chief witness in a murder case.

The pornography empire cultivated by brothers Artie and Jim Mitchell crumbles when one turns up dead and his brother confesses to shooting him; investigators question whether the shooting was premeditated.

When prison guard Donna Payant's body is discovered at a landfill, a medical examiner uses a "signature" clue to link her death to a murder the same examiner investigated 10 years earlier.

When a 9-year-old girl vanishes on her way to school, the entire community helps with the search; detectives believe her mother may be involved, and a hidden fingerprint seals the case.

The investigation of a murder case in New Jersey is stalled until a similar attack occurs on a state trooper in Maine.

A young woman goes missing without leaving many clues, but the advanced technology on offer makes it possible for cat hairs and insects to help build an image of the abductor.

Blood spatter analysis and an investigation lead police to the truth when a pregnant woman is found dead in her home.

A mother is determined to discover what happened when her daughter is injured in a hit-and-run accident.

Forensic science and deductive reasoning determine what happened to a mother and daughter while they were on a shopping spree.

Exploring how an American hit single from 1966 - "The Cheater" by Bob Kuban and the In-Men - foreshadowed the demise of the group's lead singer, Walter Scott.

Eight years after a man confessed to the murder of a young woman, another man claims that he committed the crime, and investigators must use forensic evidence to determine the true killer.

A massive explosion claims the life of a California farmhand, and authorities think it's an accidental death, but analysis of debris shows it's a bomb; investigators have few suspects until they hear ominous rumors about a jealous rage.

When a beautiful college student is stabbed to death in her Knoxville apartment, suspicion immediately falls on her roommate; a bloody shoe print left by the killer exposes a murderer with no history of violence and no reason to kill.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

The anchors share the latest stories about significant events that take place across the world and interview prominent figures.

Numerous suspects emerge after someone starts targeting law enforcement officers in a peaceful Texas county.

An Illinois mother and her two young children are brutally murdered in their beds, and lurid threats are spray painted all over the walls of the crime scene.

A young Texas teenager and her boyfriend are brutally attacked on Valentine's Day; she is found dead while her boyfriend escapes; the case goes cold for nearly 50 years before a new forensic test exposes a family man with a dark secret.

Three Indiana construction workers are found shot on a work site.

A Texan who vows to live a reformed life after being released from prison is subsequently convicted of murder, despite insisting his innocence, so he uses forensic science from behind bars to try to prove his case.

An extremely successful California career woman keeps falling ill and doctors can't determine why, then after she dies they still have no explanation until they find a key figure in her life has been lying about his past.

The body of a 24-year-old criminology student is found wrapped in a blanket alongside a desolate road in Brooklyn, N.Y.; police discover that the bouncer at a bar is her killer.

When a 79-year-old woman is found shot to death in her home, investigators initially suspect her husband or a violent neighbor; shell casings recovered at the scene and a high-tech database reveal an unlikely killer.

Although a group of teenage thugs are suspected of attacking two boys on a fishing trip, there is no solid evidence until a murky fishing hole provides some answers.

When young prostitute's body turns up in an Ohio waterway, authorities have one tiny clue which could point to her killer, but face huge challenges due to her policemen clients and DNA evidence being washed away.

In a small South Carolina town in 1991, 17-year-old Crystal Faye Todd, a popular high school student, is raped, murdered and dumped in a deserted field; with few leads, authorities test the DNA of several friends, and one match shocks everyone.

In a groundbreaking case using animal DNA, investigators use forensic testing on a cat to help them solve the case of a woman who vanished from her home on Prince Edward Island.

A look into the 1984 Oregon food poisonings, where detectives track down the outbreak to a cult which aims to use germ warfare to take down the government.

A woman is found dead from a gunshot wound and police suspect her husband, however, forensic teams prove what really happened and the truth is stranger than fiction.

After American Atheists founder Madalyn Murray O'Hair disappears, the discovery of a mutilated body helps police catch the culprit.

Two people witness a truck driving over an unconscious man and flee into a nearby bar, but when the police turn up, the truck, the man and the witnesses are gone.

Insect evidence helps to solve the mystery of a woman found dead near a river bank.

A girl who is abducted and then released soon afterwards uses her knowledge of forensics to lead police to the kidnapper.

A trash collector finds a severed human leg in a trash bin but police cannot use conventional methods of victim identification; investigators turn to toxicology and DNA tests to find the murder-mutilator.

A coroner finds telltale clues on the badly burned body of a murder victim, sending police in pursuit of a couple of killers.

A man is arrested and convicted for a series of sexual assaults in Indiana; years later, forensic developments reveal new facts about the case.

The murder of a young Seattle couple puzzles investigators until the victims' dog, Chief, leads police to the killer.

A handsome young doctor's fiancee experiences severe illness after revealing that she is pregnant, and launches her own investigation to determine if the doctor is somehow responsible.

A seemingly model citizen turns out to be a serial killer.

An abandoned, still-running car leads investigators to a body with unusual marks and a DNA trail that lead to the killer.

Police find fragments of deleted computer files leading them to suspect a woman's suicide is really murder.

A look into the 1984 Oregon food poisonings, where detectives track down the outbreak to a cult which aims to use germ warfare to take down the government.

A woman is found dead from a gunshot wound and police suspect her husband, however, forensic teams prove what really happened and the truth is stranger than fiction.

After American Atheists founder Madalyn Murray O'Hair disappears, the discovery of a mutilated body helps police catch the culprit.

Two people witness a truck driving over an unconscious man and flee into a nearby bar, but when the police turn up, the truck, the man and the witnesses are gone.

Insect evidence helps to solve the mystery of a woman found dead near a river bank.

A girl who is abducted and then released soon afterwards uses her knowledge of forensics to lead police to the kidnapper.

A trash collector finds a severed human leg in a trash bin but police cannot use conventional methods of victim identification; investigators turn to toxicology and DNA tests to find the murder-mutilator.

A coroner finds telltale clues on the badly burned body of a murder victim, sending police in pursuit of a couple of killers.

A man is arrested and convicted for a series of sexual assaults in Indiana; years later, forensic developments reveal new facts about the case.

The murder of a young Seattle couple puzzles investigators until the victims' dog, Chief, leads police to the killer.

A handsome young doctor's fiancee experiences severe illness after revealing that she is pregnant, and launches her own investigation to determine if the doctor is somehow responsible.

A seemingly model citizen turns out to be a serial killer.

An abandoned, still-running car leads investigators to a body with unusual marks and a DNA trail that lead to the killer.

Police find fragments of deleted computer files leading them to suspect a woman's suicide is really murder.

Stories from across the world and refreshing conversations with Audie Cornish.

Stories from across the world and refreshing conversations with Audie Cornish.

He calls himself "B.T.K." which stands for "Bind, Torture, Kill" and for decades this bloodthirsty serial killer terrifies Wichita as he murders again.

For years the BTK killer plays a cat and mouse game with law enforcement and the media taunting them as he seeks the attention he craves.

The summer of 1985 was one of the hottest Los Angeles had seen in a century. But terrified residents weren't sleeping with the windows open; a killer known as the "Night Stalker" was on the loose.

A tip from a teenage boy leads to the identity of the Night Stalker and twenty-four hours later a mob of angry citizens track him down and capture him.

Desperate for answers community members live in terror waiting for the man dubbed the Co-Ed Killer to strike again.

In April 1973, Edmund Kemper, 24, murders six coeds in and around the city of Santa Cruz, Calif., shaking the community to its core.

A suspicious neighbor gives police a break in a cold case.

A family suspects their teenage daughter's new friends were involved in her disappearance.

When a 62-year-old man opens a car restoration business and becomes seriously ill, his doctors cannot find the cause, but forensics can; identification of a highly toxic metal in the victim's blood leads to his poisoner.

When a 6-year-old disappears, her father becomes the prime suspect; he fails a polygraph test and even confesses, but 10 years later, the investigation gets turned on its head.

Investigators build a makeshift tent around a woman's body and use super glue fumes to lift the killer's palm print from the victim's skin.

The disappearance of a mail-order bride proves suspicious when detectives learn that two of the Texas husband's previous wives had died in mysterious circumstances.

A jeweler's search through old sales records helps police find likely suspects in the murder of elderly couple Edward Kowalzck and Gertrude Thompson.

A garbage bag leads police to a child's killer.

An investigation into the disappearance of a young woman uncovers a tooth that helps police solve a crime without a body.

The sensitive nose of a forensic examiner sniffs out murder.

Discovering that an assault suspect is left-handed is crucial to a police investigation dating back 16 years.

Forensic scientists try to find a way to "lift" the serial number from a shotgun that's their only clue in a case.