He inhabits his two characters very well, slipping into Adam's despondent skin as easily as he finds Anthony's brash confidence. Whatever you make of the film, there's no denying that this is some of the best work Gyllenhaal has done in his career to date. The final shot is less cathartic than outright puzzling, underscoring the completely alien life into which Adam has stumbled once he chose to hunt down Anthony. In fact, the film ends just when a more mainstream, accessible version of this story might begin. Enemy is very much what you make of it: it's packed with ideas that are never fully explored, about lives never lived and the notion of identity, which audiences can pick apart at their own leisure. Anyone looking for easy answers or a clear message will be disappointed. The resulting film, soaked in shades of yellow, is moody and considered, its pace bordering on the languid as Adam stumbles through his existential crisis. He frets to his mother (a nicely-cast Isabella Rossellini) about the possibility that he has a twin, and finds himself in a worryingly intimate situation with Anthony's pregnant wife Helen (Sarah Gadon), but high drama proves elusive until the final ten minutes or so. But Villeneuve has chosen a determinedly glum, very philosophical approach to Adam's dilemma. There are many ways to play a scenario like this one: Enemy could easily have been a broad farce (just add in pratfalls and double-takes), or a heart-stopping thrill ride (mix in life-threatening cases of mistaken identity). Adam becomes obsessed with meeting Anthony, and soon their lives become irretrievably entangled. Turns out he has a doppelganger: a not entirely successful actor by the name of Anthony St. But everything in his humdrum existence changes when he watches an obscure movie in which, for a brief moment, he spots himself. History professor Adam Bell (Jake Gyllenhaal) leads a dull, repetitive life: he lectures unappreciative kids about totalitarian dictatorships, has bursts of largely uncommunicative sex with his maybe-girlfriend Mary (Mélanie Laurent), and otherwise shuffles through the day in a lethargic haze. It's fascinating, mostly, but also slow- moving and, ultimately, frustrating. Denis Villeneuve's Enemy, a psychologically-charged mystery that's more thoughtful than thrilling, explores the idea that there's someone else in the world who shares your face but has, seemingly, nothing else to do with you. From The Prince And The Pauper through to Sweet Valley High, literature and fiction has held a particular fascination with the notion of doppelgangers: two (or more) individuals who are physically identical and yet fundamentally different, whether in personality or social station.