Line of Duty, Series 5, BBC One review - already it's dark, dirty and dangerous

Congratulations to Stephen Graham, guest-starring in this fifth season of BBC One’s Line of Duty, for still being alive at the end of episode one, a favour not routinely granted to headline names in Jed Mercurio’s

diabolical labyrinth of deception. Then again, death needn’t necessarily be the end, as we were reminded when the late and exceptionally unlamented ACC Derek Hilton, the sleazy string-puller from series four, repeated on us here like a bad oyster.

Mercurio isn’t just telling a story, he’s spinning a kind of Game of Villains epic that stretches out to unknowable horizons. Just as the ghost of the appalling Dot Cottan may never be fully exorcised, so the evil that Hilton did lives after him, in the hapless personage of PC Maneet Bindra (Maya Sondhi). She was suborned by Hilton, we learned, using the chronic indebtedness of her cousin Bilhan Malhotra as leverage to prise out details of what Ted Hastings and his AC-12 anti-corruption unit were up to. Now, Malhotra has been exposed as the inside man who assisted the murderous van robbery with which this first episode opened. With his connivance, John Corbett’s black-balaclava’d gang were able to grab a huge stash of seized heroin which had been due for disposal, killing three police officers in the process. The fact that a badly injured female officer was spared a fatal bullet in the head may prove to be a crucial fragment of information.

Graham (pictured right) plays Corbett with a harsh, eyes-narrowed focus, as if he’s peering deep into the cracks of every situation or scanning the barcode on the soul of whoever he’s talking to. Graham played Al Capone in Boardwalk Empire with a kind of rumbustious, extrovert ruthlessness, but here he’s like a squat chunk of granite, unreadable and unforgiving. His Liverpool accent is cranked up and pared down until it cuts like a Stanley knife. When he enters a room, everybody suddenly feels off balance.

Obviously it’s early days and everything will change, but on one level this is a story of inter-gang rivalry. Corbett wants to sell the stolen heroin to a guy called Slater (Barry Aird), but Slater says it was his already before it was sequestered by the cops. Corbett offers to go 50-50. Slater offers him 10 per cent. As a test of nerve and loyalty, Corbett sends his right-hand woman Lisa McQueen (Rochenda Sandall) to close the deal. He’s been having doubts about her loyalty and commitment, and one more strike and she’ll be out.

Around all this is wrapped a parallel mystery involving an undercover police operation, Operation Peartree, which AC-12 stumbled across during their investigations. While the cast may change around them, DS Arnott and DI Fleming (Martin Compston and Vicky McClure) have slipped back seamlessly into their roles of relentless, humourless inquisitors, never satisfied with anybody’s answers about anything. Their antennae were tweaked by the defensive demeanour of Alison Powell, the officer in charge of Peartree. But it was under indignant questioning from Ted Hastings (Adrian Dunbar at his most righteously Old Testament) that she admitted Peartree was out of control, and that she’d lost contact with her embedded undercover officer (Corbett and his gang, pictured below).

We thought we knew the identity of the latter, but we were wrong. However, Ted Hastings knows a lot more than he’s letting on, which may account for the self-conscious theatricality of some of his outbursts. When you pull on the end of Mercurio’s ball of string, a whole lot of horrors are going to tumble out.

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