Collateral, series finale, BBC Two - Carey Mulligan hares to the finish

In a revelatory interview for the Royal Court’s playwright’s podcast series, David Hare admits to a thin skin. In his adversarial worldview, to take issue with him is – his word – to denounce him. He’s quite a denouncer himself, of course.

In Collateral (BBC Two), the denunciations were directed at something rotten in the state of, in no particular order, the Church of England, the Labour Party, the British Army, the Fourth Estate, the security services, the body politic, the establishment, old Uncle Tom Cobbleigh and all. Somewhere in there there was also a police procedural. This has been a new pasture for Hare. In broad outline, he presented his audience with three niggling difficulties.

One, the playwright in him was unable to repress an instinct for planting his own thought bubbles in the mouths of his characters, who ended up sounding like him. An illegal immigrant or an asylum seeker or an MI5 apparatchik or a chippy detective or a posh addict might spout whingey op-eds or incandescent tweets about the state of the nation. In the third episode, to take one trivial example, an elderly disabled woman in a council flat complained of not being able to get through to social services on the phone: “two hours of Johann Strauss,” she moaned. She’d have no more cracked this urbane witticism, with its implied derision for Vienna's schmaltzy waltzes, than earned selection for the Zambian trampoline squad.

Two, in the first episode there was a motorway pile-up of coincidences which placed the ex of a rebel Labour MP, and the current girlfriend of another of his exes, at the scene of the murder of an Iraqi asylum seeker in a quiet London street. As a way of gathering in the loose strands of Hare’s ticklist of hot-button themes, this felt ungainly enough to start with. What became even more perplexing by the final episode was that these elements had virtually nothing to do with the main plot except to act as illustration slides in a lecture. (Pictured below: Kae Alexander and Nicola Walker).Three, Carey Mulligan. Carey Mulligan as an ex-Olympic pole vaulter is a leap of faith. Carey Mulligan as a hard-bitten detective inspector is a zero-gravity moon jump. DI Kip Glaspie – weird name, but then TV dramas have to call coppers names that aren’t shared with real coppers – marched from interview to crime scene to meeting armed with a knowing quip to bung back over her shoulder for absolutely every occasion. Being idealistic and highly intelligent, wanting to “put something right”, she was in effect David Hare in drag pole-vaulting over a high bar and into the bosom of the Met. “Somehow I felt I had authorisation,” she said to her boss (Ben Miles) who accused her of insubordinately offering asylum to an Iraqi witness. “I discerned it – it was in the air.” Spoken like an untrue detective.

And yet the final episode did manage to hit a high gear and roar towards the finish as the police closed in on the traffickers, accidentally blew the cover of MI5’s mole, and bore down on the murderer, who administered her own retribution. There was a great intricacy of bluffing and blackmailing, not all of it in the upstairs café at Tate Britain. Kip’s interview with Berna (Maya Sansa) had a genuine whiff of actual cordite, plus a recommendation that we all watch more Turkish art house movies. There was also much to savour in the placard-waving ideological face-off between Simm’s maverick backbencher David Mars and Saskia Reeves as ballbreaking party leader Deborah Clifford, who revealed a flair for an equestrian metaphor: “I’m riding a horse that’s been shot through the legs," she said, "and I’ll do anything to get it up and running again.”

There was contagious talk of systems. “The system’s beaten me, truly,” said Rev Jane Oliver (Nicola Walker, very moving). “Isn’t that the point of systems?” asked Mars's assistant (Jacqueline Boatswain). “To outwit them?” Knotted-up and inward-facing, both the Church of England and the Labour Party, those former guarantors of civic compassion, were both shown to be suffering from systemic paralysis, albeit not particularly in relation to the main plot.And then there was the army. Into the character of Captain Sandrine Shaw (Jeany Spark, pictured above), whose unwarranted nude scene was meant to symbolise her being stripped of all illusions, Hare loaded his thoughts about the tragedy of our military, dishonoured by its adventures in Afghanistan and Iraq and now preying on its own. (Robert Portal was chilling as Shaw’s very superior officer). “I regret not being good,” she wrote by way of valediction. Her blood dripped down wallpaper illustrating, for extra irony, a traditional British blood sport. However bankrupt an institution, the army would definitely have informed Sandrine’s mother in person.

The excellent acting piled on the flesh. In the end Collateral, a drama about damage, asked us to think about who gets to live in the UK, to be born in it, to die for it, and to kill for it. And of course, which slippery cynics get to run away from it when the shit hits the fan. It was probably too much to think about in four hours. This was Hare’s cluttered civics class lecture, addressed to whom it may concern. Lesson one: always check your email trail.

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@JasperRees