The murders of three Arlington, Texas, teenagers in 1985 and the subsequent homicide investigation are discussed.

Season 3 premiere. An attack on a Pennsylvania family that left only one survivor is discussed.

"Went 2 Talk 2 Rob" are the last words 15-year-old Becky Stowe writes before she slips out, never to be seen again. Did she run away or did her boyfriend Rob make her disappear? Two years go by before the truth about Becky is finally revealed.

After a young girl describes her mother's killer as being a ninja, police attempt to work out the truth behind the child's description as they put the murderer behind bars.

The police manage to track down the killer of a disabled Denver woman and they attempt to establish whether or not she was killed for money or if there was a more personal motive for her death.

The strangulation death of an 8-year-old girl in Ocean Shores, Wash., is investigated.

The leading advocate for the controversial science of cold fusion is beaten to death and investigators run the full gamut of suspects, from corporate executives to drug-crazed burglars, to find his killer.

When 10-year-old Katie Collman is murdered in a small Indiana town, a shocking confession catapults this crime into national news. Was Katie murdered to keep her quiet about something she saw? An unusual clue leads investigators to the conclusion.

The investigation into the murder of a young North Carolina woman is recounted.

The killer of a Santa Monica art teacher remains at large for years as police use every trick in their arsenal to finally hunt him down.

In 1996, teenaged Joey Martin sneaks out of his bedroom window to watch a comet from a cabin in the woods-and disappears. Despite multiple leads, there is no sign of Joey until 2008 when a young detective uncovers the shocking story of Joey's fate.

Soon after Mardi Gras in Mobile, Alabama, an 18-year-old freshman is found shot to death in the woods behind campus. Detectives take a hard look at several suspects, but thirty years go by before a stunning confession cracks the case.

FBI office manager Melissa Mooney is found murdered in her home. After taking a hard look at several promising suspects, the case goes cold. Two years later, a reexamination of the case leads to an unlikely killer who was hiding in plain sight.

When tycoon Andrew Kissel is stabbed to death in his Greenwich mansion, detectives are faced with a long list of suspects. Practically everyone who knew the victim has a motive for murder. Ultimately, a secret money trail reveals the guilty party.

The 1994 murder of Missy Grubaugh is discussed.

Investigators in San Diego search for a serial killer after six females are slain in 1990.

The lethal poisoning of a waitress in Florida is investigated.

The murder of a young woman in her Portland, Ore., apartment is investigated.

In 1984, terrifying screams pierce the Florida night. A day later, a woman's body is found, stabbed to death. Detective Larry Tosi faces a host of suspects, but when the killer is caught, no one will be more shocked than Tosi himself.

The murder of a gun advocate in Kentucky and the investigation that nabbed her killer are discussed.

The murder of a California businessman is linked to a contract killer.

In 2004, affluent Coral Gables couple, John & Susan Sutton, are attacked at home. Susan doesn't survive. Investigators look at an adulterous business partner and an angry client before cell phone records lead to a shooter with ties to the family.

In 1985, an LA County Sheriff is gunned down in his vehicle. Investigators drill down the slain cop's list of enemies with no results. In 1999, a multi-agency task force shines a new light on the old case, illuminating a culprit who defies belief.

The murders of three women in three Iowa hotels between 1993 and 1997 and the investigation that nabbed the killer are discussed.

The murder of a man in Maine is connected to a cold case.