Every year in Britain, more than 600 people commit murder. The majority of these killers will eventually be sent to Gartree Prison in Leicester, which is home to Europe's largest population of life-sentenced prisoners. A brand new Cutting Edge documentary filmed over six months at HMP Gartree now provides an unprecedented insight into the lives of convicted killers facing a lifetime behind bars. These men will die in prison unless they can convince the authorities they have changed and are no longer a risk to society. With unique access to Gartree's cells, landings, segregation unit and visiting rooms, Lifers explores the everyday realities of prison life for those convicted of murder. The documentary examines the psychological impact of killing, following prisoners as they try to come to terms with what they've done, with varying degrees of remorse and contrition.