James Marsh's Shadow Dancer, a coolly handled, uncommonly adult thriller, tells the story of a woman caught between loyalty to her family and the pull of two even deadlier organisations. In 1993, low-level IRA footsoldier Colette McVeigh (Andrea Riseborough) is picked up by British security forces in the aftermath of an attempt to bomb Mile End Tube station. Pressured into becoming an informant, McVeigh finds herself in a tricky position within not just her working-class Belfast community, but her own household, as mother to a young son who needed picking up from school at the same time she was supposed to liaise with her MI5 handler (Clive Owen); and as sister to a pair of fervently Republican brothers (Domnhall Gleeson, Aidan Gillen) who keep marching into the home Colette shares with her mother (Brid Brennan) and demanding she accompany them on their own assassination endeavours. The more info McVeigh gives to the Brits, the more her IRA superiors - apparently blind to the women in their ranks, except when explosives were required to be placed somewhere - are inclined to suspect one of her siblings might be the mole.
For much of the film, we're questioning where exactly its protagonist's allegiances lie. For a start, there seems to be some ambiguity over whether McVeigh meant the Mile End bomb to have gone off, or whether her leaving the device unarmed might be read as a cry for help, a single mother's bid for self-preservation at a moment - just a day or two after the 1993 peace accord signed by British PM John Major - when it appeared uncertain whether the Troubles were winding down or merely heading towards a final, deadly blowout. We're never quite certain how much McVeigh knows, and whether the security forces weren't looking in the wrong place when they approached her: Riseborough, deathly pale, puts up on the big screen a variant of that opaque acting style we witnessed from Damian Lewis in Homeland, the recent TV hit that may just have primed audiences for Shadow Dancer's narrative sophistry.
She's certainly well-matched with Owen, a proven master at playing narked, here exuding frustration with both the intransigence of a woman who'd rather play with her son than come to his table at the alloted hour, and at his own superiors (represented by Gillian Anderson as a brisk, businesslike remnant of the Thatcherite old guard), who've been pressured by Westminster into taking this investigation in an entirely new direction, leaving him equally isolated. Everyone's got their game face on here, and some time into Shadow Dancer, it becomes clear Marsh, too, is playing something of a dangerous game. Not necessarily with what the film has to say about the Troubles, which is well-documented - the source is a book by ITN reporter Tom Bradby, who wrote the screenplay and has a rather clanging cameo - but with its points of identification, which aren't always clear, and in how this information is presented to us, as a slow, measured, accumulating drip. Only in the film's final moments do the narrative pieces come together, and by then, it's too late to ask for your money back if you feel you've been cheated in some way by what you've seen.
This blithe narrative facility has been a feature of Marsh's documentary work (Wisconsin Death Trip, the Oscar-winning Man on Wire, last year's Project Nim) as well as his earlier experiment in fiction, 2005's underrated The King. Shadow Dancer is ample proof he's gained much along the way: chiefly, the understanding that atmosphere and suspense are better sustained these days in long, unbroken takes where - formally - we wait for the inevitable cut to occur, and - narratively - for the worst to happen. This holds true of the opening, following McVeigh's fateful commute on that morning in 1993, or in a later IRA hit framed against a backdrop of wide-open suburban spaces. Marsh is also unusual in believing that it's often better to say nothing and allow the viewer to weigh the assembled evidence for themselves than to shepherd them towards a conclusion with a large expositionary crook.
That's admirable, but somewhere in that last belief lurks the possibility we might, like the sheep we are when we enter the cinema, wander towards the wrong conclusion, and feel grumpy, even resentful, upon being shown the error of our ways. The trouble with Shadow Dancer is not that it hasn't been very skilfully directed (it has); it's the extent to which even those viewers who'd agree this is engrossing, intelligent viewing might emerge feeling as though they've been misdirected somehow. Like any good documentarist, Marsh knows when to hone in on a particular detail, as at a heavily policed IRA funeral, where a handgun is passed from mourner to mourner so an illicit salute can be fired off; in the melee that follows, the camera turns away to show, there on the sidelines, the mothers of this community, standing variously vulnerable, scared or helpless. Yet as Shadow Dancer's endgame demonstrates, even this apparently crystallising image proves to have been a feint, a facade. Troubles, indeed.
Shadow Dancer opens in selected cinemas from Friday.