Line of Duty fans won’t want to miss this thrilling deep dive into the secretive and high-stakes world of witness protection in ITV1 crime drama Protection, starring Happy Valley actors Siobhan Finneran and Katherine Kelly.

The six-part series begins in shocking fashion when a key witness and his wife are gunned down at the start of this Sunday’s opening episode.

DI Liz Nyles (Finneran) and her team had been watching over high-profile criminal turned informant Jimmy McLennan (Kris Hitchen) at a safe house, only for him to be murdered before he could give evidence against powerful drug lord Eddie Crowther (Alec Newman).

It was the job of Liz and colleague DS Raj Kohli (Chaneil Kular) to keep the family’s whereabouts strictly hidden, and the killing raises grave questions about the integrity of Liz’s unit. Has someone in the team been leaking information to organised crime?

‘That big event in the opening minutes draws you in immediately,’ says Finneran. ‘Then you’re ready to go on a journey with Liz, to find out what’s going on. It’s a great hook and the story is so complex – I’ve never done a job this intense.’