Season 4

An investigation into a 23-year-old Hawaiian tourist's rape and murder reveals a world of drugs and deception few vacationers ever see. And it's up to one lone detective to get the victims family some justice

South California is the perfect place to retire, but when an 84-year-old is brutally raped and murdered in her senior living community everyone is a suspect. To find her killer, the investigation goes global as the suspect does his best to slip away.

An 18-year-old runaway is found raped and strangled to death on the side of a San Diego road. Tracking down the cold-blooded killer will take years of detective work and a benign connection.

In Colorado, a lifelong bad boy comes home to finds his wife, savagely raped and strangled to death. Evidence indicates the attack is personal. But is the husband is trying to get away with murder or could someone else be involved?

Murdock Nebraska, a man returns home to find his mother and father shot to death. Nothing of value is missing. Everyone in town is stunned by the news and they begin to wonder, is the killer someone they know?

Minneapolis, Minnesota is a haven for its large gay community, until gunfire rips through the city leaving two men dead. An eyewitness leads investigators to a suspect, but soon after, an anonymous letter points to an anti-gay hate group on a mission.

Miami's Coconut Grove rarely sees trouble. Until Jos? Calvo, a family man, is shot in the head and robbed of his Rolex watch. What appears to be a random cash grab turns into a sinister mystery. Is this a robbery gone bad or a murder for hire?

Aiken, South Carolina, is a tiny peaceful town where nothing much happens. Until Jessica Carpenter, 17, is found raped and murdered in her living room. The neighborhood goes on high alert while police swing into action to catch her killer.

Austin is famous for its music scene and party spirit--until a single mother is savagely beaten in her sleep. With no leads, and a culture that distrust authority, 21 years pass before investigators get a stunning phone call that turns the case red-hot.

In one of the most notorious missing children cases, Adam Walsh, 6, steps into a stranger's car and disappears. A manhunt is launched but Adam's severed head is found two weeks later. More than a quarter of century passes before the mystery is solved.

A horrendous miscarriage of justice made all the more famous by the book The Innocent Man - Murder & Injustice in a Small Town by John Grisham. In Ada Oklahoma, 21-year-old Debbie Sue Carter is found raped, beaten and strangled in her apartment. A quest for justice thrusts Ada into the national spotlight and leaves a family wondering for a quarter of a century - who killed Debbie Carter?

Winston-Salem in 1982 is a city divided by race. And when a young white copy editor is raped and stabbed to death blocks from where she worked, the atmosphere is tense. Twenty years pass before Deborah Sykes' killer finally faces justice once and for all.

Shock waves ripple throughout Clearwater, Florida, when an attractive waitress is found on her bedroom floor stabbed 16 times. As years pass and the case goes cold, police fear DNA might not even find justice for Laurie Colannino.

A budding college football player's life is cut short when his 21st birthday party ends with his brutal murder. A gun shot to the head with a bullet wound so exact that Lexington police think it looks like a hit. But who would want to kill Trent Digiuro?

When Jim Webb, Co-Owner and Head Chef of the General Wayne Inn outside of Philadelphia, is found shot to death in his office, police hatch a plan so risky it could mean letting a killer run free forever.

A murderous attack in Park Slope, Brooklyn, leaves Sylvia Lugo dead and her girlfriend, Amanda Leach, raped and shot in the leg. Police struggle to pin down an assailant without any hard evidence, resulting in Leach being pegged as the prime suspect.

When Wharton business student Shannon Schieber is found raped and strangled to death in her Philadelphia apartment, the city errupts with outrage as it's discovered that Shannon's death is the the latest in a string of rapes in the Centre City area.

A McDonalds restaurant manager is murdered in a small Tennessee town and the police force goes into overdrive. But with a big list of suspects investigators are baffled and the case goes cold. Two years later, a tip brings them to Delma Ramsey's killers.

Palo Alto's community sympathize with wealthy property developer Ken Fitzhugh when his wife of more than 30 years, Kristine, falls to her death down the basement stairs. But police are suspicious from the get go: there is just too much blood at the scene.