A sleepy Pennsylvania town is rocked when a popular dentist is discovered lying in a pool of blood. Police uncover few clues but plenty of rumors. Was the motive money or passion? And can the police be relied upon to investigate one of their own?

A mother, Debi Whitlock, is found brutally murdered in her California home. Police discover that Debi's life was anything but peaceful. For six years Debi's mother leads a media campaign that is key to finding her daughter's killer.

In Boston, a white couple is carjacked and shot. The husband calls 911 and describes their assailant as an African-American male. Racial tensions are high as police pin down two suspects, but is there a third suspect?

Parceled into a series of plastic bags, the dismembered body Karyn Slover is found floating in an Illinois lake. An autopsy reveals she also suffered multiple gunshot wounds to the head. After 2 years and no leads, can forensic science crack the case?

A photographer from Switzerland is brutally murdered in his Los Angeles home. Blood has dripped from the ceiling, glass is everywhere, and the body of 37-year-old Roland Kuster lies face down on the floor. Can forensic science eventually solve the case?

A serial killer is on the loose in the college town of Gainesville, Florida. And although police close in on their prime suspect, they fail to establish a forensic link and the case goes cold. But can they find the culprit before he strikes again?