In 1963, 13-year-old Alison goes missing from the village of Scardale and young inspector George Bennett (Ingleby) becomes obsessed with the case. Alison's bloody clothing is eventually found (but no body) and her wealthy, pervy stepfather Philip Hawkin (Wise) is accused of her murder after Bennett finds porn photos of Alison. Forty years later, filmmaker Catherine Heathcote (Stevenson) is making a documentary about the case with extensive interviews with the retired Bennett (Jackson) who suddenly withdraws his cooperation. Obsessive herself, Catherine starts digging deeper and discovers a miscarriage of justice may have occurred that leads back to George. Based on the novel by Val McDermid.