Britain's Most Evil Killers

In January 2009, Lakhvir Singh poisoned her former lover and his fiancée. The deadly plot, driven by jealousy and revenge, ended in tragedy.

In 2011, Attila lured Alice and Tibor to his flat. Within hours, both were dead. Police uncover a shocking story of jealousy, obsession and cold-blooded murder.

In 1979, Sally Ann McGrath vanished in Peterborough. Decades later, cold case detectives exposed Paul Taylor as her killer after years of hiding his crimes.