The unbelievable murder of Carol Kennedy, a popular college professor, artist and mother.

Rocky Mountain National Park rangers question whether a woman's fatal fall was an accident or the result of an act of violence.

It was called "the trial of the century" and, decades after the polarizing case, questions remain; hear answers and insights through interviews done over the years, rare footage and revealing conversations with key players who offer new details.

A woman goes for a walk during a snowstorm and never returns.

Co-lead investigator in the Steven Avery case Tom Fassbender discusses the case and allegations investigators coerced Avery's nephew, Brendan Dassey, into making a false confession.

Two years after the disappearance of his wife, Josh Powell kills his two sons and himself; Josh's last in-depth TV interview; a 911 dispatcher discusses the emergency call placed by a social worker.

Two Tulsa brothers fight for more than 20 years to prove their innocence after they were wrongfully convicted for separate murders.

The investigation into the death of a woman whose remains were found in her Frisco, Texas, garage leads detectives to a series of suspects with connections to the victim's complicated and secretive life.

Police initially suspect natural causes as they investigate a man's death, until they learn about an unconventional love triangle, which points the investigation in a new direction.

When Susan Woods doesn't show up for work, she is soon discovered dead in her bathtub; as police search for answers, they find a trail of victims.

A man dies in a shooting incident after tempers flare in a confrontation in Montana's Glacier National Park.

Police investigate whether the shooting of a young woman in Utah was an accident or something more sinister.

Two years after the disappearance of his wife, Josh Powell kills his two sons and himself; Josh's last in-depth TV interview; a 911 dispatcher discusses the emergency call placed by a social worker.

Two Tulsa brothers fight for more than 20 years to prove their innocence after they were wrongfully convicted for separate murders.

The investigation into the death of a woman whose remains were found in her Frisco, Texas, garage leads detectives to a series of suspects with connections to the victim's complicated and secretive life.

Police initially suspect natural causes as they investigate a man's death, until they learn about an unconventional love triangle, which points the investigation in a new direction.

When Susan Woods doesn't show up for work, she is soon discovered dead in her bathtub; as police search for answers, they find a trail of victims.

A man dies in a shooting incident after tempers flare in a confrontation in Montana's Glacier National Park.

Police investigate whether the shooting of a young woman in Utah was an accident or something more sinister.

Two years after the disappearance of his wife, Josh Powell kills his two sons and himself; Josh's last in-depth TV interview; a 911 dispatcher discusses the emergency call placed by a social worker.

Two Tulsa brothers fight for more than 20 years to prove their innocence after they were wrongfully convicted for separate murders.

The investigation into the death of a woman whose remains were found in her Frisco, Texas, garage leads detectives to a series of suspects with connections to the victim's complicated and secretive life.

Police initially suspect natural causes as they investigate a man's death, until they learn about an unconventional love triangle, which points the investigation in a new direction.

When Susan Woods doesn't show up for work, she is soon discovered dead in her bathtub; as police search for answers, they find a trail of victims.

A man dies in a shooting incident after tempers flare in a confrontation in Montana's Glacier National Park.

Police investigate whether the shooting of a young woman in Utah was an accident or something more sinister.

Investigators are suspicious when a wealthy former radio DJ mysteriously disappears from his yacht in the Pacific Ocean.

A charismatic pastor's dark secrets come to light after his wife's mysterious death; the case shattered a congregation and exposed the cost of their unshakable trust.

A top-ranking officer in the Canadian military pleaded guilty to a number of crimes, from home invasions and lingerie theft to murder.

A wife and mother survives an attack in her home and a shot to the head; authorities search for a motive.

When a woman is found dead in her SUV, the investigation into her murder reveals a tangled web of sex and lies; interviews about the prominent family's dark secrets.

A look at the crimes committed by Charles Manson and his followers in 1969, including archival footage and interviews with those close to the events.

The deadly 2020 shooting at U.S. District Court Judge Esther Salas' home, which killed her son and critically injured her husband.

Investigators are suspicious when a wealthy former radio DJ mysteriously disappears from his yacht in the Pacific Ocean.

A charismatic pastor's dark secrets come to light after his wife's mysterious death; the case shattered a congregation and exposed the cost of their unshakable trust.

A top-ranking officer in the Canadian military pleaded guilty to a number of crimes, from home invasions and lingerie theft to murder.

A wife and mother survives an attack in her home and a shot to the head; authorities search for a motive.

When a woman is found dead in her SUV, the investigation into her murder reveals a tangled web of sex and lies; interviews about the prominent family's dark secrets.

A look at the crimes committed by Charles Manson and his followers in 1969, including archival footage and interviews with those close to the events.

The deadly 2020 shooting at U.S. District Court Judge Esther Salas' home, which killed her son and critically injured her husband.

Investigators are suspicious when a wealthy former radio DJ mysteriously disappears from his yacht in the Pacific Ocean.

A charismatic pastor's dark secrets come to light after his wife's mysterious death; the case shattered a congregation and exposed the cost of their unshakable trust.

A top-ranking officer in the Canadian military pleaded guilty to a number of crimes, from home invasions and lingerie theft to murder.

A wife and mother survives an attack in her home and a shot to the head; authorities search for a motive.

When a woman is found dead in her SUV, the investigation into her murder reveals a tangled web of sex and lies; interviews about the prominent family's dark secrets.

A look at the crimes committed by Charles Manson and his followers in 1969, including archival footage and interviews with those close to the events.

The deadly 2020 shooting at U.S. District Court Judge Esther Salas' home, which killed her son and critically injured her husband.

Investigators are suspicious when a wealthy former radio DJ mysteriously disappears from his yacht in the Pacific Ocean.

A random post on a social networking site changes everything about a case that put two brothers in prison for more that two decades.

The investigation into the murder of a pregnant woman leads to a former professional football player and several women associated with him.

A wife and mother is handcuffed and taken into an unmarked car by a blond woman on a Monday morning, but her family is unable to find any record of the arrest.

A chance encounter on the Pacific Coast Highway with a woman he first spoke to in a jail cell leads Keith Morrison to reexamine the mysterious death of Las Vegas casino magnate Ted Binion.

A hunting safari in Zambia's Kafue National Park ends in a nightmare when a shot rings out from the cabin of dentist Dr. Larry Rudolph and his wife Bianca.

San Diego detectives investigate the deaths of a young woman and her 10-month-old child.

A chance encounter by custom agents leads to a break in the case of a mother who disappeared days before she was supposed to move to a new city with her young son; 20 years after the incident, a witness speaks out.

A random post on a social networking site changes everything about a case that put two brothers in prison for more that two decades.

The investigation into the murder of a pregnant woman leads to a former professional football player and several women associated with him.

A wife and mother is handcuffed and taken into an unmarked car by a blond woman on a Monday morning, but her family is unable to find any record of the arrest.

A chance encounter on the Pacific Coast Highway with a woman he first spoke to in a jail cell leads Keith Morrison to reexamine the mysterious death of Las Vegas casino magnate Ted Binion.

A hunting safari in Zambia's Kafue National Park ends in a nightmare when a shot rings out from the cabin of dentist Dr. Larry Rudolph and his wife Bianca.

San Diego detectives investigate the deaths of a young woman and her 10-month-old child.

A chance encounter by custom agents leads to a break in the case of a mother who disappeared days before she was supposed to move to a new city with her young son; 20 years after the incident, a witness speaks out.

A random post on a social networking site changes everything about a case that put two brothers in prison for more that two decades.

The investigation into the murder of a pregnant woman leads to a former professional football player and several women associated with him.

A wife and mother is handcuffed and taken into an unmarked car by a blond woman on a Monday morning, but her family is unable to find any record of the arrest.

A chance encounter on the Pacific Coast Highway with a woman he first spoke to in a jail cell leads Keith Morrison to reexamine the mysterious death of Las Vegas casino magnate Ted Binion.

A hunting safari in Zambia's Kafue National Park ends in a nightmare when a shot rings out from the cabin of dentist Dr. Larry Rudolph and his wife Bianca.

San Diego detectives investigate the deaths of a young woman and her 10-month-old child.

A chance encounter by custom agents leads to a break in the case of a mother who disappeared days before she was supposed to move to a new city with her young son; 20 years after the incident, a witness speaks out.

The investigation into the death of a college student leads authorities to her theater group and a new crime that exposes the truth.

When a luxury car dealer is found dead, detectives suspect one of his lovers, but lack of evidence stalls the case for a year until one clue breaks it wide open.

A mother's death initially appears to be a suicide, but when investigators start to interview those closest to her, an evil plot emerges.

A Nebraska family's parents are murdered following the clan's Easter celebration.

When a young woman is found dead in a field on the outskirts of Green Bay, Wis., a fitness tracker helps detectives solve the mystery.

The disappearance of 19-year-old Alaska Native Sonya Ivanoff sends shockwaves through the small coastal city of Nome, Alaska; police scramble to find answers until a note is found in a stolen police vehicle telling the cops to back off or else.

Melissa Oxley wakes up to find her husband, Ben Oxley, has been shot in the head.

The investigation into the death of a college student leads authorities to her theater group and a new crime that exposes the truth.

When a luxury car dealer is found dead, detectives suspect one of his lovers, but lack of evidence stalls the case for a year until one clue breaks it wide open.

A mother's death initially appears to be a suicide, but when investigators start to interview those closest to her, an evil plot emerges.

A Nebraska family's parents are murdered following the clan's Easter celebration.

When a young woman is found dead in a field on the outskirts of Green Bay, Wis., a fitness tracker helps detectives solve the mystery.

The disappearance of 19-year-old Alaska Native Sonya Ivanoff sends shockwaves through the small coastal city of Nome, Alaska; police scramble to find answers until a note is found in a stolen police vehicle telling the cops to back off or else.

Melissa Oxley wakes up to find her husband, Ben Oxley, has been shot in the head.

The investigation into the death of a college student leads authorities to her theater group and a new crime that exposes the truth.

When a luxury car dealer is found dead, detectives suspect one of his lovers, but lack of evidence stalls the case for a year until one clue breaks it wide open.

A mother's death initially appears to be a suicide, but when investigators start to interview those closest to her, an evil plot emerges.

A Nebraska family's parents are murdered following the clan's Easter celebration.

When a young woman is found dead in a field on the outskirts of Green Bay, Wis., a fitness tracker helps detectives solve the mystery.

The disappearance of 19-year-old Alaska Native Sonya Ivanoff sends shockwaves through the small coastal city of Nome, Alaska; police scramble to find answers until a note is found in a stolen police vehicle telling the cops to back off or else.

Melissa Oxley wakes up to find her husband, Ben Oxley, has been shot in the head.

Years after a college student is murdered in her condo, calls to the police lead to the case being reopened and solved.

A Georgia couple's romantic tryst takes a deadly turn, leaving investigators stumped -- until tire treads at the scene and cell phone calls reveal a twisted plot.

A popular high school student is found murdered in her bed; two students help police solve the case.

The investigation into the death of a pregnant woman just months after she wed her high school sweetheart reveals secret lives and feuds.

A couple is murdered shortly after their wedding and police suspect a family feud is the cause; Josh Mankiewicz looks back at what started the dispute that left him floored.

A college student is found murdered in a residential neighborhood; as police search for the truth, they are stunned to learn that one of their own might be involved.

As detectives investigate a mother of two's sudden disappearance, her friends and family reveal she feared she was being stalked.

Years after a college student is murdered in her condo, calls to the police lead to the case being reopened and solved.

A Georgia couple's romantic tryst takes a deadly turn, leaving investigators stumped -- until tire treads at the scene and cell phone calls reveal a twisted plot.

A popular high school student is found murdered in her bed; two students help police solve the case.

The investigation into the death of a pregnant woman just months after she wed her high school sweetheart reveals secret lives and feuds.

A couple is murdered shortly after their wedding and police suspect a family feud is the cause; Josh Mankiewicz looks back at what started the dispute that left him floored.

A college student is found murdered in a residential neighborhood; as police search for the truth, they are stunned to learn that one of their own might be involved.

As detectives investigate a mother of two's sudden disappearance, her friends and family reveal she feared she was being stalked.

Years after a college student is murdered in her condo, calls to the police lead to the case being reopened and solved.

A Georgia couple's romantic tryst takes a deadly turn, leaving investigators stumped -- until tire treads at the scene and cell phone calls reveal a twisted plot.

A popular high school student is found murdered in her bed; two students help police solve the case.

The investigation into the death of a pregnant woman just months after she wed her high school sweetheart reveals secret lives and feuds.

A couple is murdered shortly after their wedding and police suspect a family feud is the cause; Josh Mankiewicz looks back at what started the dispute that left him floored.

A college student is found murdered in a residential neighborhood; as police search for the truth, they are stunned to learn that one of their own might be involved.

As detectives investigate a mother of two's sudden disappearance, her friends and family reveal she feared she was being stalked.

A cold-case investigator helps police determine what happened to a missing woman.

After a sudden marriage creates tension between two families, a murder exposes secrets, lies and a long-buried mystery.

A former marine who once was the hero for a woman in an abusive marriage may have let his desire to help go too far.

When an Iowa woman is attacked while home alone with her three children, the confrontation turns deadly.

A woman is found murdered after her close friend hears her screaming on the phone; the mysterious death of her boyfriend's twin brother leads investigators to a suspect.

A San Diego mother suddenly vanishes in 2014; nearly two years later, her body is found in the San Diego Bay, but medical examiners say she has only been dead for a month or two.

When a former hockey player discovers his wife murdered in their home, his daughter says she saw a burglar.

A cold-case investigator helps police determine what happened to a missing woman.

After a sudden marriage creates tension between two families, a murder exposes secrets, lies and a long-buried mystery.

A former marine who once was the hero for a woman in an abusive marriage may have let his desire to help go too far.

When an Iowa woman is attacked while home alone with her three children, the confrontation turns deadly.

A woman is found murdered after her close friend hears her screaming on the phone; the mysterious death of her boyfriend's twin brother leads investigators to a suspect.

A San Diego mother suddenly vanishes in 2014; nearly two years later, her body is found in the San Diego Bay, but medical examiners say she has only been dead for a month or two.

When a former hockey player discovers his wife murdered in their home, his daughter says she saw a burglar.

A cold-case investigator helps police determine what happened to a missing woman.

After a sudden marriage creates tension between two families, a murder exposes secrets, lies and a long-buried mystery.

A former marine who once was the hero for a woman in an abusive marriage may have let his desire to help go too far.

When an Iowa woman is attacked while home alone with her three children, the confrontation turns deadly.

A woman is found murdered after her close friend hears her screaming on the phone; the mysterious death of her boyfriend's twin brother leads investigators to a suspect.

A San Diego mother suddenly vanishes in 2014; nearly two years later, her body is found in the San Diego Bay, but medical examiners say she has only been dead for a month or two.

When a former hockey player discovers his wife murdered in their home, his daughter says she saw a burglar.

Investigators follow the trail of a seemingly untraceable late-night call as they search for the killer of businesswoman Peggy Nadell.

When a San Antonio man shoots his wife, he claims to have shot her after mistaking her for an intruder.

The investigation into 18-year-old Hannah Hill's disappearance takes unexpected turns.

The residents of a glamorous resort town are shocked when a well-known woman from a prominent family is found dead in her home.

A bombshell more than a decade after the crime reignites the investigation into the death of Sarah Pagel's mother, who was killed when Sarah was seven.

Investigators from Fort Worth, Texas, desperately search for answers after 17-year-old Carla Walker is kidnapped and murdered following a Valentine's Day dance; cutting-edge DNA technology and diligent police work lead detectives to her killer.

The security cameras at the home of a wife and mother of three's home may hold the key to solving the mystery of her disappearance.

Investigators follow the trail of a seemingly untraceable late-night call as they search for the killer of businesswoman Peggy Nadell.

When a San Antonio man shoots his wife, he claims to have shot her after mistaking her for an intruder.

The investigation into 18-year-old Hannah Hill's disappearance takes unexpected turns.

The residents of a glamorous resort town are shocked when a well-known woman from a prominent family is found dead in her home.

A bombshell more than a decade after the crime reignites the investigation into the death of Sarah Pagel's mother, who was killed when Sarah was seven.

Investigators from Fort Worth, Texas, desperately search for answers after 17-year-old Carla Walker is kidnapped and murdered following a Valentine's Day dance; cutting-edge DNA technology and diligent police work lead detectives to her killer.

The security cameras at the home of a wife and mother of three's home may hold the key to solving the mystery of her disappearance.

Investigators follow the trail of a seemingly untraceable late-night call as they search for the killer of businesswoman Peggy Nadell.

When a San Antonio man shoots his wife, he claims to have shot her after mistaking her for an intruder.

The investigation into 18-year-old Hannah Hill's disappearance takes unexpected turns.

The residents of a glamorous resort town are shocked when a well-known woman from a prominent family is found dead in her home.

A bombshell more than a decade after the crime reignites the investigation into the death of Sarah Pagel's mother, who was killed when Sarah was seven.

Investigators from Fort Worth, Texas, desperately search for answers after 17-year-old Carla Walker is kidnapped and murdered following a Valentine's Day dance; cutting-edge DNA technology and diligent police work lead detectives to her killer.

The security cameras at the home of a wife and mother of three's home may hold the key to solving the mystery of her disappearance.

A teenager disappears from her friend's house before being found dead.

After teenagers Rachel Shoaf and Sheila Eddy are convicted of murdering their 16-year-old friend, Skylar Neese, Skylar's parents discuss the night she disappeared; Rachel Shoaf's therapist, Patricia Bailey, shares her thoughts.

A beloved former firefighter is found dead in his garage; a neighbor's home security camera may provide answers.

A man from Iowa is shot to death while sleeping in bed next to his fiancee; coincidences and quick thinking lead to surprising information regarding the killer's motive.

When two women call 911 after hearing someone break into their apartment, their call for help holds the key to solving the mysterious murder of a young graduate student named Katie Sepich.

A 40-year-old Minnesota woman is shot to death in her bed while her husband and teenage daughter are home, leaving investigators to wonder who would want her dead.

A couple's anniversary celebration ends in murder during what appears to have been a home invasion, but investigators believe the suspect might be connected to the victim.

A teenager disappears from her friend's house before being found dead.

After teenagers Rachel Shoaf and Sheila Eddy are convicted of murdering their 16-year-old friend, Skylar Neese, Skylar's parents discuss the night she disappeared; Rachel Shoaf's therapist, Patricia Bailey, shares her thoughts.

A beloved former firefighter is found dead in his garage; a neighbor's home security camera may provide answers.

A man from Iowa is shot to death while sleeping in bed next to his fiancee; coincidences and quick thinking lead to surprising information regarding the killer's motive.

When two women call 911 after hearing someone break into their apartment, their call for help holds the key to solving the mysterious murder of a young graduate student named Katie Sepich.

A 40-year-old Minnesota woman is shot to death in her bed while her husband and teenage daughter are home, leaving investigators to wonder who would want her dead.

A couple's anniversary celebration ends in murder during what appears to have been a home invasion, but investigators believe the suspect might be connected to the victim.

A teenager disappears from her friend's house before being found dead.

After teenagers Rachel Shoaf and Sheila Eddy are convicted of murdering their 16-year-old friend, Skylar Neese, Skylar's parents discuss the night she disappeared; Rachel Shoaf's therapist, Patricia Bailey, shares her thoughts.

A beloved former firefighter is found dead in his garage; a neighbor's home security camera may provide answers.

A man from Iowa is shot to death while sleeping in bed next to his fiancee; coincidences and quick thinking lead to surprising information regarding the killer's motive.

When two women call 911 after hearing someone break into their apartment, their call for help holds the key to solving the mysterious murder of a young graduate student named Katie Sepich.

A 40-year-old Minnesota woman is shot to death in her bed while her husband and teenage daughter are home, leaving investigators to wonder who would want her dead.

A couple's anniversary celebration ends in murder during what appears to have been a home invasion, but investigators believe the suspect might be connected to the victim.

A woman's death is initially ruled a suicide, but when a new investigation begins, police begin to suspect murder.

Nearly 40 years after a high school senior is found stabbed to death in her car after visiting the mall days before Christmas, investigators identify the killer.

When a South Carolina coroner arrives at the scene of a car accident to find his friend deceased, he notices some unusual markings on her face and begins to think her death looks suspicious.

The disappearance of a young woman from Bend, Ore., leads to an intense manhunt after the suspect embarks on a two state crime spree.

After a 15-year-old girl disappears, investigators discover a creek where the local teenagers hang out that may hold the answer to her disappearance.

The murder of former NBA star and hometown hero Lorenzen Wright sends shockwaves through the city of Memphis; insiders speak out about new developments in the lengthy search for justice.

When a hard-charging boss in Arizona is shot to death, police uncover a complex web of bruised egos in his professional life and a trail of broken hearts in his personal life.

A woman's death is initially ruled a suicide, but when a new investigation begins, police begin to suspect murder.

Nearly 40 years after a high school senior is found stabbed to death in her car after visiting the mall days before Christmas, investigators identify the killer.

When a South Carolina coroner arrives at the scene of a car accident to find his friend deceased, he notices some unusual markings on her face and begins to think her death looks suspicious.

The disappearance of a young woman from Bend, Ore., leads to an intense manhunt after the suspect embarks on a two state crime spree.

After a 15-year-old girl disappears, investigators discover a creek where the local teenagers hang out that may hold the answer to her disappearance.

The murder of former NBA star and hometown hero Lorenzen Wright sends shockwaves through the city of Memphis; insiders speak out about new developments in the lengthy search for justice.

When a hard-charging boss in Arizona is shot to death, police uncover a complex web of bruised egos in his professional life and a trail of broken hearts in his personal life.

A woman's death is initially ruled a suicide, but when a new investigation begins, police begin to suspect murder.

Nearly 40 years after a high school senior is found stabbed to death in her car after visiting the mall days before Christmas, investigators identify the killer.

When a South Carolina coroner arrives at the scene of a car accident to find his friend deceased, he notices some unusual markings on her face and begins to think her death looks suspicious.

The disappearance of a young woman from Bend, Ore., leads to an intense manhunt after the suspect embarks on a two state crime spree.

After a 15-year-old girl disappears, investigators discover a creek where the local teenagers hang out that may hold the answer to her disappearance.

The murder of former NBA star and hometown hero Lorenzen Wright sends shockwaves through the city of Memphis; insiders speak out about new developments in the lengthy search for justice.

When a hard-charging boss in Arizona is shot to death, police uncover a complex web of bruised egos in his professional life and a trail of broken hearts in his personal life.

A woman's death is initially ruled a suicide, but when a new investigation begins, police begin to suspect murder.

Investigators find an unlikely suspect in a woman's death; actor Ricky Gervais talks about his life, fame and hosting the Golden Globe Awards.

The discovery of an Army captain's death in her El Paso, Texas, home shakes her tight-knit military community.

A look at the growing homeless epidemic in America, including a tour of Skid Row, the nation's epicenter of homelessness; residents of the San Fernando Valley and Venice discuss the influx of homeless people into their neighborhoods.

When a woman disappears after an encounter on a train, her family hires detectives to investigate.

The mystery of a successful real estate entrepreneur killed by a car bomb spans nearly two decades.

When a young, handsome veterinarian is found dead in his home in Montana, the mystery remains unsolved for nearly two decades.

When 18-year-old Anjelica "AJ" Hadsell disappears, the investigation into her inner circle reveals a sinister betrayal; featuring interviews with AJ's stepfather Wesley Hadsell and two of her friends.

Investigators find an unlikely suspect in a woman's death; actor Ricky Gervais talks about his life, fame and hosting the Golden Globe Awards.

The discovery of an Army captain's death in her El Paso, Texas, home shakes her tight-knit military community.

A look at the growing homeless epidemic in America, including a tour of Skid Row, the nation's epicenter of homelessness; residents of the San Fernando Valley and Venice discuss the influx of homeless people into their neighborhoods.

When a woman disappears after an encounter on a train, her family hires detectives to investigate.

The mystery of a successful real estate entrepreneur killed by a car bomb spans nearly two decades.