Ten years after a young girl is kidnapped and killed on her way home from a costume party, a mistake comes to light.

The murder of two grandparents tears a family apart; two decades later, a detective races to solve the cold case that has haunted him since he was a child.

A rookie cold-case detective investigating the brutal stabbing death of a bullied teenager notices a clue in an old crime scene photo that may help solve the 27-year-old case.

A killer's book about his shady past becomes the key to solving the 29-year-old cold case of two high-school sweethearts and three other unsolved murders, leading police to believe he could be the Zodiac Killer.

A college student disappears from his graveyard shift at a gas station; new forensic technology and the discovery of an illegal drug ring in a squeaky-clean town helps police solve the case two decades later.

After 33 years, police finally unravel the case of a law-enforcement officer who was shot execution-style in his home.