With vigilante Tom Marwood still at large and targeting Luther and the people closest to him, things have never been tougher for the maverick detective – and the situation rapidly gets worse when he is accused of crimes he has not committed.

With no support from his old colleagues and girlfriend Mary in the dubious custody of Stark and Gray, he has no choice but to work outside the law if he is to bring Marwood down. But with the killer’s demands escalating and time running out, Luther faces an impossible choice … and risks losing everything.

Series 3 Episode 4 airs at 9pm on Tuesday 23 July on BBC One. To whet your appetite, here are ten teasing lines of dialogue from the ep…

» ‘What is it with John Luther and the people he loves?’

» ‘I’m after Marwood – then I’m done.’

» ‘Your conscience has killed more people than I have.’

» ‘If you’re going to be on the run, you’re going to have to lose the coat.’

» ‘This looks more like the scene of a violent abduction.’

» ‘What’s the plan, Stan?’

» ‘I was the police … but I’m not anymore.’

» ‘He really does need the world to love him, doesn’t he?’

» ‘John is as innocent as I am culpable.’

» ‘If you ever betray him like this again, I’ll kill you and eat you.’

> Order Series 3 on DVD on Amazon.

> Buy the Series 1-2 boxset on Amazon.

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Watch the Series 3 trailer…