Episode 6

Luke Aikens settles the argument about whether the conspiracy is real by strapping David Budd into a suicide vest with a dead man's switch. The police are called. But nobody believes him, least of all the officers who now suspect him of being part of the plot because of his hidden friendship with Apsted. He admits the lie: he concealed the connection so he would not be the fall guy.

The scene is being watched. Budd guesses MI5 is listening. He feeds them a false location for the kompromat and waits. Longcross comes to collect it and walks into a flat booby-trapped with pepper spray; blinded and arrested, he is the first real piece of the puzzle to fall. The stand-off outside ends with Vicky running to her husband to stop the police firing on him. Still wearing the vest, Budd leads everyone back to his flat, where Vicky hands over the kompromat and the blank rounds that clear him. An explosives officer takes the vest off him, and he walks away to finish the job.

What he finds is the worst kind of answer. Lorraine Craddock, his own boss, is Aikens's insider. She confesses to leaking Montague's movements and enabling the assassination, and admits she wanted Budd on the detail because his military and PTSD history made him the perfect scapegoat. Nadia Ali is interviewed again and gives the interrogation its strangest turn: she built the devices herself, and remembered what Budd let slip about his children while he was disarming her vest on the train; the details went straight into the school plot. Aikens paid for the bomb that killed Montague, and RIPA 18 would have given the police the powers to go after him. The kompromat finally surfaces, apparently via Commander Sampson, who tells Budd the Prime Minister and the Director General of MI5 are finished.

Jed Mercurio wrote it, John Strickland directed, and the ensemble does the closing work justice: Richard Madden's Budd, Sophie Rundle's Vicky, Pippa Haywood's Craddock, Matt Stokoe's Aikens, Anjli Mohindra's Nadia, Stephanie Hyam's Dyson, Michael Shaeffer's Longcross, Ash Tandon's Sharma and Gina McKee's Sampson.

Budd starts occupational health treatment for his PTSD. The show gives him that, along with a family that came back for him. He keeps breathing. After six episodes of being used, that feels like a win.