A series of California fires puts investigators on the hunt for a serial arsonist. After years of dogged investigation, an unpopular theory points to a disturbing culprit.

A serial killer on the loose in Spokane prompts investigators to take a new look at an old clue.

A delivery man guns down an affluent couple, with their only son barely escaping. The investigation reveals a greedy relative with a motive too close to home. And when a recent victim of burglary is found shot to death in her car, the investigation uncovers a killer the victim trusted without question - the police officer who came to her aide.

When high-ranking oil executive Sidney Reso is kidnapped, an intensive manhunt turns up few clues. Cryptic letters and phone calls send investigators racing to catch the kidnappers, hoping to bring Reso home alive.

A young woman disappears after a flat tire makes her pull over; a man is murdered while minding his neighbor's property.

In rural Wisconsin, a local eccentric is murdered in his home; A serial killer targets the elderly in Lake Elsinore, California.

A husband and wife are found shot to death on a deserted stretch of highway. Phone records help detectives uncover a murder-for-hire plot that went horribly wrong, and discover that one of their victims is also their prime suspect. Next, when a 20-year-old woman is found murdered near a freeway exit ramp, the residents of San Diego demand justice. But when a trusted police officer is identified for the crime, the community is shaken to its core.

A young couple is gunned down on a lover's lane in Georgia; A husband and wife are shot to death in their suburban Chicago home before the killer sets the house on fire.

Detailing the crimes of serial killer Keith Jesperson, also known as the "Happy Face Killer."

A wealthy widow is slain, and the victim's records provide the means to find her killer.

A young boy is killed in the middle of the night, and his own mother is convicted of the crime. Years later, an author investigates a convicted murderer for her upcoming novel, and gets a confession that re-opens that case file and eventually, sets the mother free.

A 40-year-old mother disappears from her home in the middle of the night, and police chase multiple leads before coming up empty. Almost a year goes by until they investigate a very unlikely suspect - a high-school neighbor with an affinity for older women. Then, a teenage boy is murdered in his home and detectives believe his campaign against teen gang activity led to his death. But the community is horrified when police arrest one of their "model citizens" for ordering the hit.

A judge and his wife are slain in their home, and the suspects range from common criminals to politicians.