Retired drama teacher Kathy Gillcrist embarks on a journey to find her biological parents. Her worst fears come to fruition when she discovers police want her father for one of the most infamous mass murders in Maryland state history.

An army surgeon, Jeffrey MacDonald, is the lone survivor of a brutal 1970 home invasion that claims the lives of his wife and daughters. But authorities doubt his story of murderous hippies and believe MacDonald is the culprit.

Five young people disappeared over a span of four years in the rural area of Lewis-Clark Valley, along the Idaho-Washington border. Investigators search for links to the mysterious cases.

In 2001, a mother of five is found shot in the head in her own minivan. Investigators have little physical evidence and struggle to make an arrest. As the children grow up, the family becomes divided over who killed the beloved soccer mom.

A 19-year-old coed leaves her apartment and never returns. When her body is found in a desert river basin, police and internet sleuths alike wonder if she was a victim of an alleged killer known as The Zombie Hunter.

Four teenage girls are brutally murdered in a yogurt shop in North Austin, Texas, in 1991, in what becomes the biggest mass murder in Austin history. The investigation that follows drags on for years, and even when police make an arrest, justice is not guaranteed.

Virginia firefighters respond to a house fire in Upperville, Virginia where they discover the body of a local journalist. The fire destroys any hope for evidence, but the victim's social media history leads police down a rabbit hole.

In Florida, friends and family are stunned after an esteemed criminal law professor is executed in his garage. Investigators follow a series of leads taking them on a statewide hunt in search of the murderous masterminds.

College student Tammy Zywicki vanishes in 1992 after her car breaks down on the highway. Family and friends scramble to find her, but when her body is found 500 miles from where she vanished there are very few clues pointing to her killer. Police struggle with dead-end leads and suspects who don't pan out. New DNA technology promises to finally crack the case decades later. As her family clings to the last of their hope, the fear is that it may be too little too late for justice.

In 2007, a 19-year-old woman is brutally murdered in the small town of Winnsboro, TX; the ensuing investigation reveals the small town has a few wolves masquerading in sheep's clothing. Some secrets come to light, but others may be buried forever.

After a single mother fails to show up for work, police find her brutally stabbed and her 14-year-old daughter missing from their home in an affluent gated community. Everyone fears she's in danger, but what they uncover is darker than they could have imagined.

For years, a serial killer stalks the most vulnerable and least suspecting victims: retirees. However, when a 91-year-old woman survives, she helps break the case wide open, leading to the capture of one of the most prolific serial killers of modern times.

In 2021, police find a retired couple stabbed repeatedly in their home on the New Jersey shore. They witness a mysterious figure coming and going on security footage, which leads them to a suspect who is very close to home with a desire for revenge.

[Murder by the Book] On June 12, 1991, outgoing Jackie Galloway is found strangled and bound with ritualistic knots. Police investigate suspects in her inner circle but are shocked when a chance encounter with a prowler leads them to discover the murderer is a budding serial killer.

[20-Year Murder Mystery] Six-year-old beauty queen JonBenét Ramsey is found murdered in her Boulder, Colorado home in 1996. Investigators try to unravel if she was killed in a kidnapping-gone-wrong, by a home intruder or by one of her own family.

A premiere fishing boat explodes into flames just off shore, stunning the small fishing town of Craig, Alaska. After fighting the flames, state troopers discover the remains of a young family and few clues as to could have set the ship blaze.

After doting mother Cheryl Coker vanishes from Riverside, OH, numerous searches turn up nothing; as police take a closer look at the case, they uncover some disturbing information.

A young couple's toddler vanishes while the family is enjoying an impromptu camping trip in Leadore, Idaho. Investigators and private detectives work around the clock to find the missing boy, only to come back to his parents.

In 1984, the body of a 14-year-old girl turns up on the beach in San Diego, and police think it relates to the murder of another teen. A clue yields an unbelievable suspect.

In 1982, in an upscale suburb of Rochester, New York, a Kodak executive returns home and finds his wife dead with an ax in her head. People believed a madman was on the loose, so 40 years later when police make an arrest, everyone is stunned at who stands trial for the murder.

[Gone Without a Trace] In 2011, a 10-month-old baby girl goes missing from her home in Kansas City. The family fears she's been kidnapped by a drifter, only to be accused by the police of being responsible for her disappearance.

Police investigate the shooting deaths of millionaires Brad and Andra Sachs in their home in 2014 and track a series of clues in a chase to find the couple's killer.

After a fire chief's wife's burned body is discovered, an autopsy reveals she died from a gunshot wound to the head, and the arson investigation turns into a hunt for her killer.

A celebratory night turns deadly for a Texas family when they are gunned down at home. When investigators uncover a conspiracy, it will test one man's ability to forgive as he fights to save the criminal mastermind from the death penalty.

In the summer of 2000, bags full of body parts start appearing all over the San Francisco Bay Area. Investigators follow the trail of grisly clues to a secret cult carrying out a sinister scheme.