When a scientist is murdered in his home, detectives try to figure out why his wife and son were left unharmed.

An intruder breaks into a lawyer's home, murders his wife and blinds him; in a search for the truth, the lawyer questions his troubled son as a possible suspect.

A man who was arrested and tried three times for the death of his wife of four months talks about the case.

A mother of three married to a missionary is found dead on Valentine's Day; the investigation into the murder reveals answers close to home.

Former DEA agent Andrew Hogan details his search for Mexican drug lord Joaquín "El Chapo" Guzmán with never-before-seen videos and photographs.

When a small-town Alabama resident is murdered in his home, rumors involving a local pastor begin to swirl as the truth ends up turning the community upside down.

After losing a hotly contested custody battle, a woman disappears with her 11-month-old daughter; the child's father searches four continents for almost two decades before reaching an emotional conclusion.

The 2006 poisoning death of former Russian spy and businessman Alexander Litvinenko; an interview with the prime suspect in the case.

The discovery of a 19-year-old's car abandoned on a bridge in New Jersey turns into a missing person case that evolves into a monthslong homicide investigation; police discover a plot involving money, close friends and a fatal betrayal.

A man steals millions of dollars by conning numerous women and businesses over 25 years; one woman brings together a group of his victims to hold him accountable and make him face justice.

Insiders close to an Idaho woman accused of murdering her husband speak out for the first time on television; new details emerge, including never-before-seen bodycam and jailhouse footage.

A doctor ingests a lethal chemical, causing friends to wonder if it was an attempt at suicide or if he was poisoned -- until a love triangle is uncovered.

A Kentucky man is convicted of murdering his co-worker; the mystery is considered solved until a stunning disclosure years later turns the closed case upside down.

After losing a hotly contested custody battle, a woman disappears with her 11-month-old daughter; the child's father searches four continents for almost two decades before reaching an emotional conclusion.

The 2006 poisoning death of former Russian spy and businessman Alexander Litvinenko; an interview with the prime suspect in the case.

The discovery of a 19-year-old's car abandoned on a bridge in New Jersey turns into a missing person case that evolves into a monthslong homicide investigation; police discover a plot involving money, close friends and a fatal betrayal.

A man steals millions of dollars by conning numerous women and businesses over 25 years; one woman brings together a group of his victims to hold him accountable and make him face justice.

Insiders close to an Idaho woman accused of murdering her husband speak out for the first time on television; new details emerge, including never-before-seen bodycam and jailhouse footage.

A doctor ingests a lethal chemical, causing friends to wonder if it was an attempt at suicide or if he was poisoned -- until a love triangle is uncovered.

A Kentucky man is convicted of murdering his co-worker; the mystery is considered solved until a stunning disclosure years later turns the closed case upside down.

After losing a hotly contested custody battle, a woman disappears with her 11-month-old daughter; the child's father searches four continents for almost two decades before reaching an emotional conclusion.

The 2006 poisoning death of former Russian spy and businessman Alexander Litvinenko; an interview with the prime suspect in the case.

The discovery of a 19-year-old's car abandoned on a bridge in New Jersey turns into a missing person case that evolves into a monthslong homicide investigation; police discover a plot involving money, close friends and a fatal betrayal.

A man steals millions of dollars by conning numerous women and businesses over 25 years; one woman brings together a group of his victims to hold him accountable and make him face justice.

Insiders close to an Idaho woman accused of murdering her husband speak out for the first time on television; new details emerge, including never-before-seen bodycam and jailhouse footage.

A doctor ingests a lethal chemical, causing friends to wonder if it was an attempt at suicide or if he was poisoned -- until a love triangle is uncovered.

A Kentucky man is convicted of murdering his co-worker; the mystery is considered solved until a stunning disclosure years later turns the closed case upside down.

A man is shot and killed while picking up his daughter for a court-ordered visit.

An Idaho woman's affair with her married boss leads to a lethal confrontation.

When a mother is murdered in a home invasion the day before her best friend is shot outside the place they both worked, investigators suspect the crimes are linked.

Investigators seek answers when a prosecutor and a district attorney and his wife are murdered within a couple of months of each other.

When three people are found dead on the same day in a Kentucky town, investigators know it isn't a coincidence; years pass before there's an arrest as the case continues to divide the community.

A woman suspects poisoning when she finds her husband of five months dead on the bedroom floor with no clue as to what happened.

The parents of a missing South Carolina woman speak out about her disappearance.

A man is shot and killed while picking up his daughter for a court-ordered visit.

An Idaho woman's affair with her married boss leads to a lethal confrontation.

When a mother is murdered in a home invasion the day before her best friend is shot outside the place they both worked, investigators suspect the crimes are linked.

Investigators seek answers when a prosecutor and a district attorney and his wife are murdered within a couple of months of each other.

When three people are found dead on the same day in a Kentucky town, investigators know it isn't a coincidence; years pass before there's an arrest as the case continues to divide the community.

A woman suspects poisoning when she finds her husband of five months dead on the bedroom floor with no clue as to what happened.

The parents of a missing South Carolina woman speak out about her disappearance.

A man is shot and killed while picking up his daughter for a court-ordered visit.

An Idaho woman's affair with her married boss leads to a lethal confrontation.

When a mother is murdered in a home invasion the day before her best friend is shot outside the place they both worked, investigators suspect the crimes are linked.

Investigators seek answers when a prosecutor and a district attorney and his wife are murdered within a couple of months of each other.

When three people are found dead on the same day in a Kentucky town, investigators know it isn't a coincidence; years pass before there's an arrest as the case continues to divide the community.

A woman suspects poisoning when she finds her husband of five months dead on the bedroom floor with no clue as to what happened.

The parents of a missing South Carolina woman speak out about her disappearance.

The life of the charming con man who went by the name Clark Rockefeller.

A couple goes on a scuba-diving vacation in the British Virgin Islands; on the final dive of the trip, one of them surfaces -- but the other does not.

A young woman's murder remains unsolved until someone comes forward to reveal her own harrowing story.

Secrets emerge and a family is torn apart when a cop's wife is shot to death in her bed.

The investigation into the disappearance of a Marine's 19-year-old wife reveals a secret love triangle and multiple suspects.

A love triangle leads to years of stalking, property destruction, threats, and murder.

The father of an Alabama teenager calls the police after he returns home to find his son had thrown a party, leaving the place trashed; 11 minutes after the deputy leaves the house, another 911 call is placed reporting a shooting at the residence.

The life of the charming con man who went by the name Clark Rockefeller.

A couple goes on a scuba-diving vacation in the British Virgin Islands; on the final dive of the trip, one of them surfaces -- but the other does not.

A young woman's murder remains unsolved until someone comes forward to reveal her own harrowing story.

Secrets emerge and a family is torn apart when a cop's wife is shot to death in her bed.

The investigation into the disappearance of a Marine's 19-year-old wife reveals a secret love triangle and multiple suspects.

A love triangle leads to years of stalking, property destruction, threats, and murder.

The father of an Alabama teenager calls the police after he returns home to find his son had thrown a party, leaving the place trashed; 11 minutes after the deputy leaves the house, another 911 call is placed reporting a shooting at the residence.

The life of the charming con man who went by the name Clark Rockefeller.

A couple goes on a scuba-diving vacation in the British Virgin Islands; on the final dive of the trip, one of them surfaces -- but the other does not.

A young woman's murder remains unsolved until someone comes forward to reveal her own harrowing story.

Secrets emerge and a family is torn apart when a cop's wife is shot to death in her bed.

The investigation into the disappearance of a Marine's 19-year-old wife reveals a secret love triangle and multiple suspects.

A love triangle leads to years of stalking, property destruction, threats, and murder.

The father of an Alabama teenager calls the police after he returns home to find his son had thrown a party, leaving the place trashed; 11 minutes after the deputy leaves the house, another 911 call is placed reporting a shooting at the residence.

When a husband and father disappears, detectives uncover a love triangle and a twisted plot through social media and text messages.

After a young Army veteran disappears, detectives uncover a cryptic 911 call placed 11 days before she went missing, which exposes a twisted story -- and the truth.

The battle between a wife and a mistress for one man's heart leads to a deadly car chase.

Money and greed tear two close-knit California families apart.

Mysterious deaths occur inside a traveling commune, starting an investigation that lasts more than a decade; two sisters -- former commune members -- reveal stories that involve lies, lust and greed.

Private investigator and former police officer Taylor Wright vanishes, but detectives think there is more to the story after her girlfriend receives strange text messages from Taylor's phone.

An advocate for missing and murdered Indigenous women searches for answers in the disappearance of her niece and exposes cracks in law enforcement.

When a husband and father disappears, detectives uncover a love triangle and a twisted plot through social media and text messages.

After a young Army veteran disappears, detectives uncover a cryptic 911 call placed 11 days before she went missing, which exposes a twisted story -- and the truth.

The battle between a wife and a mistress for one man's heart leads to a deadly car chase.

Money and greed tear two close-knit California families apart.

Mysterious deaths occur inside a traveling commune, starting an investigation that lasts more than a decade; two sisters -- former commune members -- reveal stories that involve lies, lust and greed.

Private investigator and former police officer Taylor Wright vanishes, but detectives think there is more to the story after her girlfriend receives strange text messages from Taylor's phone.

An advocate for missing and murdered Indigenous women searches for answers in the disappearance of her niece and exposes cracks in law enforcement.

When a husband and father disappears, detectives uncover a love triangle and a twisted plot through social media and text messages.

After a young Army veteran disappears, detectives uncover a cryptic 911 call placed 11 days before she went missing, which exposes a twisted story -- and the truth.

The battle between a wife and a mistress for one man's heart leads to a deadly car chase.

Money and greed tear two close-knit California families apart.

Mysterious deaths occur inside a traveling commune, starting an investigation that lasts more than a decade; two sisters -- former commune members -- reveal stories that involve lies, lust and greed.

Private investigator and former police officer Taylor Wright vanishes, but detectives think there is more to the story after her girlfriend receives strange text messages from Taylor's phone.

An advocate for missing and murdered Indigenous women searches for answers in the disappearance of her niece and exposes cracks in law enforcement.

The investigation into a businessman's murder leads to an arrest, but as friends and neighbors rally around the accused, it begins to look like they have the wrong man.

A 64-year-old man is charged with murder after shooting two unarmed teenagers who broke into his home.

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.

After finding his wife and two children dead, a former Indiana state trooper spends 13 years trying to clear his name.

The murder of a California mother beloved by four men reopens a mystery surrounding another young woman's death that occurred decades earlier.

As detectives struggle to find leads in the murder of a college student, the perpetrator strikes again.

A soon-to-be bride is caught in the middle of a twisted murder plot that has detectives questioning if she played a role in it.

The investigation into a businessman's murder leads to an arrest, but as friends and neighbors rally around the accused, it begins to look like they have the wrong man.

A 64-year-old man is charged with murder after shooting two unarmed teenagers who broke into his home.

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.

After finding his wife and two children dead, a former Indiana state trooper spends 13 years trying to clear his name.

The murder of a California mother beloved by four men reopens a mystery surrounding another young woman's death that occurred decades earlier.

As detectives struggle to find leads in the murder of a college student, the perpetrator strikes again.

A soon-to-be bride is caught in the middle of a twisted murder plot that has detectives questioning if she played a role in it.

The investigation into a businessman's murder leads to an arrest, but as friends and neighbors rally around the accused, it begins to look like they have the wrong man.

A 64-year-old man is charged with murder after shooting two unarmed teenagers who broke into his home.

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.

After finding his wife and two children dead, a former Indiana state trooper spends 13 years trying to clear his name.

The murder of a California mother beloved by four men reopens a mystery surrounding another young woman's death that occurred decades earlier.

As detectives struggle to find leads in the murder of a college student, the perpetrator strikes again.

A soon-to-be bride is caught in the middle of a twisted murder plot that has detectives questioning if she played a role in it.

When a mother of five is found dead in her bedroom, her family believes a crazed killer is to blame.

Detectives find a message written in blood during a murder investigation.

A woman claims to have been abducted from her multimillion-dollar home, leaving more than 150 investigators to search for her.

A community comes together to search for a young woman who goes missing from a Halloween party.

Convicted murderer Drew Peterson speaks out about the murder of his third wife and the disappearance of his fourth wife in his first network TV interview in more than a decade; insiders close to the case speak out, including Stacy Peterson's sister.

When a soldier who just returned from Afghanistan is gunned down on the side of the road in Kentucky; detectives quickly uncover a secret that could solve the case.

An investigation of abuse allegations against one of the owners of religious reform school Circle of Hope.

When a mother of five is found dead in her bedroom, her family believes a crazed killer is to blame.

Detectives find a message written in blood during a murder investigation.

A woman claims to have been abducted from her multimillion-dollar home, leaving more than 150 investigators to search for her.

A community comes together to search for a young woman who goes missing from a Halloween party.

Convicted murderer Drew Peterson speaks out about the murder of his third wife and the disappearance of his fourth wife in his first network TV interview in more than a decade; insiders close to the case speak out, including Stacy Peterson's sister.

When a soldier who just returned from Afghanistan is gunned down on the side of the road in Kentucky; detectives quickly uncover a secret that could solve the case.

An investigation of abuse allegations against one of the owners of religious reform school Circle of Hope.

When a mother of five is found dead in her bedroom, her family believes a crazed killer is to blame.

Detectives find a message written in blood during a murder investigation.

A woman claims to have been abducted from her multimillion-dollar home, leaving more than 150 investigators to search for her.

A community comes together to search for a young woman who goes missing from a Halloween party.

Convicted murderer Drew Peterson speaks out about the murder of his third wife and the disappearance of his fourth wife in his first network TV interview in more than a decade; insiders close to the case speak out, including Stacy Peterson's sister.

When a soldier who just returned from Afghanistan is gunned down on the side of the road in Kentucky; detectives quickly uncover a secret that could solve the case.

An investigation of abuse allegations against one of the owners of religious reform school Circle of Hope.

A mother, who seemed to be happily married, was found dead in her backyard spa.

An Indiana mother is found asphyxiated in her basement gym.

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.

The investigation into the disappearance of a mother of three in Colorado reveals she was living a double life.

After a young mom is found dead on the side of a country road, 40 miles from her Knoxville home, investigators scramble to figure out how she ended up there.

The mystery of a Florida hotel owner's disappearance confounds family, friends and the detectives investigating the case.

A mother, who seemed to be happily married, was found dead in her backyard spa.

An Indiana mother is found asphyxiated in her basement gym.

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.

The investigation into the disappearance of a mother of three in Colorado reveals she was living a double life.

After a young mom is found dead on the side of a country road, 40 miles from her Knoxville home, investigators scramble to figure out how she ended up there.

The mystery of a Florida hotel owner's disappearance confounds family, friends and the detectives investigating the case.

A mother, who seemed to be happily married, was found dead in her backyard spa.

An Indiana mother is found asphyxiated in her basement gym.

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.

The investigation into the disappearance of a mother of three in Colorado reveals she was living a double life.

After a young mom is found dead on the side of a country road, 40 miles from her Knoxville home, investigators scramble to figure out how she ended up there.

The mystery of a Florida hotel owner's disappearance confounds family, friends and the detectives investigating the case.

When remains are found amid the rubble after a house fire, authorities soon discover the incident was no accident.

A tale of sex, betrayal and murder: Inside the deadly love triangle where three became a crowd.

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.

The Valseca siblings' lives are changed when their father is taken hostage in an orchestrated abduction.

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 29-year-old woman goes missing.

Police investigate whether the murder of a South Florida attorney is connected to a web of fraud, betrayal and more than $1 billion in missing money.

When remains are found amid the rubble after a house fire, authorities soon discover the incident was no accident.

A tale of sex, betrayal and murder: Inside the deadly love triangle where three became a crowd.

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.

The Valseca siblings' lives are changed when their father is taken hostage in an orchestrated abduction.

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 29-year-old woman goes missing.

Police investigate whether the murder of a South Florida attorney is connected to a web of fraud, betrayal and more than $1 billion in missing money.

When remains are found amid the rubble after a house fire, authorities soon discover the incident was no accident.

A tale of sex, betrayal and murder: Inside the deadly love triangle where three became a crowd.

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.

The Valseca siblings' lives are changed when their father is taken hostage in an orchestrated abduction.

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 29-year-old woman goes missing.

Police investigate whether the murder of a South Florida attorney is connected to a web of fraud, betrayal and more than $1 billion in missing money.

Authorities investigate the killing of a small-town fire chief.

A foreign exchange student and soccer player's participation in a dangerous game leads to deadly consequences.

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.

A man who was recently acquitted of the murder of his ex-girlfriend's 12-year-old son tells his story; interview with the victim's mother and key players in the case.

When a wife calls 911 to report her husband has been shot on a country road in Texas, officers rush to the scene.

When 19-year-old Anton Black dies while being taken into police custody, the community seeks justice; a yearlong "Dateline" investigation looks at the officer at the center of the case and missed warning signs.

Authorities investigate the killing of a small-town fire chief.

A foreign exchange student and soccer player's participation in a dangerous game leads to deadly consequences.

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.

A man who was recently acquitted of the murder of his ex-girlfriend's 12-year-old son tells his story; interview with the victim's mother and key players in the case.

When a wife calls 911 to report her husband has been shot on a country road in Texas, officers rush to the scene.

When 19-year-old Anton Black dies while being taken into police custody, the community seeks justice; a yearlong "Dateline" investigation looks at the officer at the center of the case and missed warning signs.

Authorities investigate the killing of a small-town fire chief.

A foreign exchange student and soccer player's participation in a dangerous game leads to deadly consequences.

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.

A man who was recently acquitted of the murder of his ex-girlfriend's 12-year-old son tells his story; interview with the victim's mother and key players in the case.

When a wife calls 911 to report her husband has been shot on a country road in Texas, officers rush to the scene.

When 19-year-old Anton Black dies while being taken into police custody, the community seeks justice; a yearlong "Dateline" investigation looks at the officer at the center of the case and missed warning signs.

A brilliant woman who rose from poverty and became a successful criminal defense attorney is murdered; investigators look into her clients and follow a bizarre string of clues.

When a Chicago woman from a big family goes missing, investigators begin to suspect a man in her life is full of secrets.

Lester Holt reports on the mysterious 2005 disappearance of Ray Gricar, a district attorney in Pennsylvania who investigated sex-abuse claims made against Jerry Sandusky in 1998.

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.

A California woman's two former husbands are mysteriously murdered, nearly 20 years apart.

When Tina Sandoval disappears, her parents and loved ones spend years searching for her; a secret she was keeping may lead to clues about what happened to her.

As actress Aasha Davis' career takes off, her sister and brother-in-law go missing.

A brilliant woman who rose from poverty and became a successful criminal defense attorney is murdered; investigators look into her clients and follow a bizarre string of clues.

When a Chicago woman from a big family goes missing, investigators begin to suspect a man in her life is full of secrets.

Lester Holt reports on the mysterious 2005 disappearance of Ray Gricar, a district attorney in Pennsylvania who investigated sex-abuse claims made against Jerry Sandusky in 1998.

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.

A California woman's two former husbands are mysteriously murdered, nearly 20 years apart.

When Tina Sandoval disappears, her parents and loved ones spend years searching for her; a secret she was keeping may lead to clues about what happened to her.