Season 4 - Episode Guide

In 1995, the body of a Chicago woman is found dumped on a Wisconsin highway. Was she the victim of a lover's spat turned deadly? Did she run afoul of local criminals? Investigators uncover the shocking truth behind the victim's tragic end.

Between 1993 and 1996, local detectives are on the trail of a sadistic killer who raped and murdered three women in Arkansas. Investigators discover that nothing is cut and dried in these cases.

In 1995, 8-year-old Maria Piceno of Lemoore, California, is abducted near her home. When her body is recovered, the search for a missing girl turns into a hunt for a vicious killer. Could one woman's searing memories be the key to a shocking truth?

In 1999, Theresa Wesolowski of Germantown, WI is found with 46 stab wounds. Unraveling the complex mystery, investigators find a tiny clue that finally nails the killer, hiding in plain sight.

In 1985, a young military wife and two of her three little girls are viciously murdered in their home. In a twisted case filled with unusual suspects, the man who gets convicted goes free. But nothing is what it seems.

In 1994, the brutalized body of a young mother is found in a 55-gallon trash barrel. Did she get caught in a love triangle, or did a coworker's obsession go to far? When the shocking truth is untangled, a vicious killer faces final justice.

In 1991, the brutalized body of a San Diego girl is found in a weed-choked canyon. Could a close encounter with a church-going couple reveal a dark secret and the identity of a child killer? Detectives unearth a shocking truth no one can believe.

April, 2004, the dismembered body of a chef is found in trash bags along a highway. Detectives grill everyone from an estranged wife to a blade-happy sous-chef. Finally, the bones give investigators the twisted answer to a bloody puzzle.

In June 1993, a California mother of two is found strangled in her home. Was she silenced by her estranged husband? An obsessed coworker? A fledgling serial killer? Undaunted, a veteran detective uncovers evidence that brings a killer to justice.

In 2006, a 20-year-old woman is brutally gunned down while walking home from her shift at a Scottsdale, Arizona, nightclub. Could her death be connected to a violent shooting spree plaguing the area? A tip reveals the gunman's shocking identity.

On a winter morning in 1993, a beloved veterinarian and his wife and son are viciously gunned down in their rural Kentucky home. Investigators leave no stone unturned as the bitter truth behind this tragic, triple slaying is revealed.

In 2001, a mother of triplets is found strangled in her Puyallup, Washington, home. Was she the victim of dangerous obsession, or a classic love triangle? As investigators piece together the victim's final moments, a shocking killer is revealed.

In 1982, a naval officer dies from a mysterious illness. When toxicology reports reveal he was poisoned, naval investigators sift through a ship of thousands and countless theories before the truth behind the victim's painful death is revealed.