Rhys is desperately trying to save his career, in the final episode of the medical crime-drama. He’s convinced he’s been made a scapegoat to cover the mistake made by the Counter Terrorism branch.

Nikki speaks to Isra again as she’s a key eyewitness. She’s staying with her solicitor, Hasan, since neither parent is allowed to enter the country. Nikki and Isra form a bond – they are both searching for the truth. When Isra’s brother suddenly dies in hospital, Nikki breaks the news to her. Accusations fly and paranoia is heightened. Was his sudden death the work of the police, a grotesque attempt to stop the truth from coming out?

Meanwhile, Harry is convinced the police are withholding information regarding “Jane Doe”. Using cutting-edge techniques, he eventually discovers her true identity: she was a police officer working undercover for the drug squad. Due to the short notice the armed police were given, they didn’t know she was a fellow officer.

Nikki returns to the terraced house to reconstruct events while Leo performs the post mortem on Melik. Leo discovers that the bullet that killed Melik was fired by the gun that everyone assumed Melik himself was firing. Nikki realises that it was Isra who fired the gun – first at the police, then at her brother. Further examination reveals that Isra had been contacting extremist groups via her brother’s email and bank accounts, groomed by Hasan.

Isra, meanwhile, has gone missing. Hasan provides her with a bomb to strap around herself as she prepares to go clubbing, but Isra has doubts. Will the police be able to get there in time?

Thursday 16 October
9.00-10.00pm BBC ONE