A Lululemon employee was found stabbed to death inside one of the company's Maryland stores. Evidence eventually pointed to a suspect on the inside.

Video shows new evidence and untold stories from the night a gunman opened fire on a country music festival from his Las Vegas hotel room, killing 58 people.

A pregnant 22-year-old disappeared just before her due date. Investigators found the newborn baby girl alive, but there was no sign of her mother.

A mysterious tip led Oklahoma police to a hotel room, where they found a missing teenage boy and a married state senator.

A 19-year-old New Jersey woman vanished just before Christmas. Her car was found abandoned. The missing persons case soon turned into a homicide investigation.