Joanne Dennehy is serving a life prison sentence after murdering three men in Peterborough. Detectives share the intimate details of the investigation.

Andrew Scanlan's body was found in a woods, weeks after he was reported missing in 2006. Detectives recount how they found the murderer.

Detective Chief Superintendent Gull is faced with five young murdered women who are found in the Suffolk countryside; the ensuing manhunt becomes an international media circus.

Detectives share the details of their investigation into the `Canal Killer', John Sweeney. He was convicted of murdering two of his girlfriends in 2011.