Director/co-writer Leigh Janiak’s disturbing variation on the ‘cabin in the woods’ horror movie starts in the realm of Polanski-esque paranoia, slides into Cronenbergian body horror then swerves into alienating sci-fi in its final stages. After a mysterious beam of light sweeps across their post-nuptial bedroom in the early hours, Bea (Rose Leslie) exhibits subtle behavioural changes that make her new husband, Paul (Harry Treadaway) doubt that she’s still the woman he married.
Sleepwalking, a shredded nightdress and mysterious marks on Bea’s inner thighs are the physical manifestations, but then Paul catches his wife rehearsing some quotidian dialogue in front of the bathroom mirror, as if she’s now only pretending to be who she once was. Their wavering American accents and starkly contrasted acting styles notwithstanding, British actors Leslie and Treadaway extract plenty of existential doubt and genuinely distressing emotion from what is essentially a claustrophobic two-hander. Janiak has succeeded in making what she calls ‘an elevated genre story’, yet much of its frightening psychological ambiguity is erased by a disappointingly conventional ending.