John Luther

Detective Chief Investigator John Luther is a legendary figure on the force both for his dedication and his ingenious approaches to solving cases. However, the horrors of Luther's job have given rise to emotional demons which often put him at odds with colleagues and loved ones. Because of this, he constantly breaches protocol and uses unorthodox (and sometimes illegal) methods, such as breaking into properties without warrants to find clues or violently threatening suspects or witnesses. He is also given to belligerent fits of anger. Nevertheless, he is known to hate firearms, and he refuses to kill or directly cause the death of suspects.

Luther returns from leave to investigate the double murder of Alice Morgan's parents, and quickly realises that she committed the crime. However, Morgan's methodical destruction of evidence keeps Luther from conclusively proving her guilt. A peculiar relationship develops between Luther and Morgan, and Luther approaches her for help on occasion. Morgan insinuates herself into Luther's relationship with Zoe with the intention of helping their marriage, yet her means only further complicate Luther's personal problems.

When Zoe is shot and killed by Luther's best friend, the corrupt Detective Chief Inspector Ian Reed, Luther – known for his violent temper – is blamed for the murder because Reed sets up the crime scene to implicate him. Luther subsequently becomes the focus of a citywide manhunt. Events transpire during which Alice kills Reed during a confrontation between him, on one side, and her, Luther, and Zoe's boyfriend Mark on the other, at a deserted Waterloo station. After providing proof that Reed murdered Zoe, Luther is allowed to return to the service, where he has now been assigned to the reorganized Serious and Serial Crime Unit, headed by DSU Schenck.

At the start of the second series, Luther has moved into an unmaintained flat at the Aylesbury Estate and shows suicidal tendencies. Luther also desires to leave the Met. He is approached by Caroline Jones, the wife of one of his former suspects, who asks him to locate her delinquent daughter, Jenny. When Luther tracks down Jenny and rescues her from a pornography shoot, the production's backers, Toby Kent and his grandmother, "Baba", violently pressure the inspector to hand her back. Rather than doing so, Luther strikes an illegal deal to provide them with information, in exchange for setting Jenny free. When Jenny kills Toby in self-defence, Luther manages to cover up her crime and threatens Baba with a visit from Alice if she continues to harass Jenny and her mother.

Idris Elba said of his character, "You know when you watch the news and someone has killed their children? And your instinct is to be like, 'Oh, if I got my hands on them'? Well, his instinct is to do that but he's a police officer. And when he does get his hands on them, he doesn't necessarily follow procedure. He will be as vindictive as the criminal".[2]