In 2008, 16-year old Meghan Landowski is found stabbed to death. A seemingly open and shut case turns into a months' long whodunit. Police methodically eliminate suspects in their hunt for a young girl's killer.

In 2001, 20-year old ranger Carrie Nelson is found beaten to death in a park office. The senseless killing turns into a five year long whodunit. Investigators turn to science as they track down an elusive and unlikely killer.

For eight years, the Bike Path Killer terrorized women in the Buffalo area - committing seven rapes and two murders. Then, without explanation, the attacks stopped. After a 12-year absence, the Bike Path Rapist resurfaces.

Human remains found in a sewer are identified as Tristan Jensen, a 14-year-old boy who was reported missing. Investigators find it hard to believe that another teenager could be the prime suspect in one of the most gruesome murders they have ever seen.

A suburban Oklahoma town is rocked by the brutal stabbing murder of 27-year-old Gary Larson and the rape of his girlfriend. The attacker leaves a trail of bloody footprints in Larson's house and investigators must follow the footsteps to catch the killer.

25-year-old waitress Corey Parker is found dead in her apartment bedroom with over 100 stab wounds to her body. After two long years of intense investigation, detectives finally zero in on a suspect. But the crafty killer knows he's being watched.