A new spate of nightmarish murders brings DCI John Luther to once again face the depths of human depravity on the streets of London; as the body count rises, Luther attempts to catch a killer and save his own neck.
With his friend in peril and a young woman kidnapped by the relentless serial killer, Luther tries to protect the innocent while preventing Cornelius' violent revenge from consuming him.
Reeling from the death of his friend, Luther races to save the others from Cornelius' terrible retribution; with Luther's increasing absence from the case, Halliday heads the hunt for a killer on the loose.
Luther takes a leave of absence from the police; when an old colleague brings him a shocking piece of news, he is drawn into investigating the crimes of a gruesome killer.
Luther investigates a twisted fetishist who is murdering women in a horrific echo of an unsolved case from the 1980s, but Superintendent Stark does not approve of his unorthodox policing.
News of a murder interrupts Luther's date with Mary; Ripley must investigate the Jared Cass murder alone.
A vigilante killer is determined to punish past offenders; the campaign pushes Luther to his limits.
Luther returns to work; a failed art student wants to emulate a Victorian killer; Luther agrees to help a widow.
Luther is determined to protect Jenny; Luther must investigate seemingly motive-free murders.
Luther's life spirals out of control; a killer's actions are ruled by dice.
Det. John Luther returns to work after the traumatic arrest of a serial killer; Luther investigates the murder of the parents of a former child genius.
Luther must outsmart a sniper on a mission to gun down police officers; Luther discovers Alice has been investigating him.
Luther must catch a satanic occult killer accused of kidnapping and murdering a young mother; when Zoe's boyfriend is assaulted, he assumes Luther is the one who did it.
Henry Madsen wakes up from his coma, putting Luther's career in jeopardy; three girls are found murdered, forcing Luther to put his personal concerns aside.
When Luther is framed for murder the only person he can turn to for help is Alice Morgan.