When does Shirley Henderson sleep? This well-crafted – if a little repetitive – British film sees the first true lead role for this excellent, versatile and omnipresent Scottish actress. Here, Henderson plays Kath, a woman whose sister has disappeared from her home town amid the fishing industries and morbid seascapes of Morecambe Bay. Frustrated by the limp police investigations, Kath herself scours CCTV footage to try to find an answer. McKoen makes much photographically of the grim mud flats and decaying industry of this north-western corner. Ultimately, though, the film feels most like a superior thriller made for television – and McKoen’s parallel of the Bay and the River Styx is a little awkward.