Looking for a group of long-missing children on a patch of moorland, podcaster Claire (Sophia La Porta) thinks she has defined her search area. But when she lays down her map in front of the police chief who once led the case, he reaches for a box and arrays five more Ordnance Surveys around it. His rejoinder – “That’s the moor” – is the equivalent of “You’re gonna need a bigger boat” in this redoubtable folk horror debut evidently inspired by the Brady-Hindley murders. You could also call it topographical horror, with director Chris Cronin using a simple set of elements – swirling mists, neolithic stones, baleful staring rams, chairs that look like baleful staring rams – to construct a formidable ambience on his fictional Holme moor.