An illicit love triangle, a wife with a double life, and one big lie lead to murder.

When an inmate and corrections officer vanish, authorities question whether it's a kidnapping or a forbidden romance.

When a boy is kidnapped riding a bike, parents, police and a blogger work to bring him home.

When a woman vanishes, police uncover her husband's dark past; the missing woman's own past comes under scrutiny.

A young woman's mysterious disappearance and the search-and-rescue operation that led police to a barn full of dark secrets.

After a young couple is murdered, their true identities lead to a shocking twist about their missing baby.

Reporting on a verdict in the case of a beloved law professor's gruesome murder.

The murder of a beloved mom sparks an international manhunt; police uncover clues in an accused killer's diary.

A former NFL player and his wife are murdered in Texas and the shocking evidence in their son's third murder trial.

A star cyclist is gunned down by a friend’s jealous girlfriend, and the international chase to find the suspect.

A North Dakota student is abducted after shopping at the mall; inside the hunt to catch a killer before he kills again.

When a woman is found murdered, a written confession gives insight into the mind of her killer.

Gypsy-Rose Blanchard's story of murder, family, romance, deception and abuse; her first interview after her release from prison.

An attempted kidnapping leads police to a killer.

Conspiracy, escorts, and murder-for-hire. An exclusive inside look at the undercover investigation.

A U.S. Army Sergeant is murdered; investigators uncover a heartless plot of adultery and greed.

A mysterious brutal murder and the bizarre home renovation that may have been the motive.

A Florida university campus is on edge when a student disappears. Police say love, lies and obsession led to murder.

A mom who would stop at nothing to find her daughter after she vanished, and the team of investigators who solved the deadly mystery.

When four young women go missing, police hunt for a serial killer roaming the interstate. John Quiñones takes us into the families’ quests for answers.

Ruby Franke, a popular YouTuber, sees her world implode after her emaciated son escapes.

When a young couple is found dead, police learn they were involved in an online feud and uncover a deadly catfishing scheme.

A teen girl vanishes after getting into an unknown vehicle. When the truth of her disappearance comes to light, the community is shocked by who is behind the violent plot.

After a small-town minister is killed at home, police uncover the dark truth of his marriage.

When a young mom goes missing, police question a pastor, the ex-husband, and even a local ventriloquist. But authorities are left wondering – who would want to harm Tricia Todd?

When two teen girls never make it home after a night out, police discover their dead bodies in the trunk of a car. Decades pass before detectives zero in on an unlikely suspect.

When a beloved celebrity hairstylist is found murdered in his own home, was it a burglary gone wrong – or something more sinister?

New developments in the case of a 20-year-old nursing student who disappeared from her Tennessee home.

After serving three decades in prison for his wife's 1987 murder, 20/20 documents a man's fight for freedom.

A new interview with Keith Papini after his ex-wife Sherri Papini served time in prison for her false kidnapping tale and mail fraud.

A couple is murdered inside their home, possibly by someone trying to hide a secret double life.

Karen Read answers questions surrounding the night at issue in her controversial trial.

The former ballerina who shot and killed her husband tells her story, in a 20/20 exclusive.