Crime to watch

Among serial killers, Israel Keyes is an enigma. When police picked him up in Texas in March of 2012, it was for the murder of 18-year-old Samantha Koenig, whom he had brazenly kidnapped from a coffee stand in Anchorage, Alaska. Once in custody, however, he confessed to other murders and bank robberies and alluded to many more crimes. He ultimately claimed to have killed up to 11 victims between 2001 and 2012, but couldn't - or wouldn't - tell the authorities exactly when and where. He told them enough, however, for them to take him seriously. Then, in December 2012, after nine months in custody, he killed himself, taking his secrets with him to the grave.

An exploration of how both the crime scenes and the serial behaviours of perpetrators leave clues about their identity for investigators to find.

A serial killer raped over 50 women, killed 10 people across Northern and Southern California, escalating crimes over years. Survivors, victims' families, detectives recount the case.

Rarely seen private journals, home videos, and emails shed new light on the 2009 disappearance of Utah mother Susan Powell;

When Tara Grinstead, a beloved teacher and former beauty queen, goes missing in Georgia, it triggers a decade-long investigation that makes national headlines.