The Guilty is set across two timelines – 2008 and present day – and tells the story of DC Maggie Brand (Tamsin Greig - Episodes, Friday Night Dinner), who investigates the disappearance of little Callum Reid whilst coping with her own young son's diagnosis with autism. Following an annual neighbourhood barbecue, Claire and Daniel Reid frantically search for Callum when they awake to find him missing. Katherine Kelly (Mr Selfridge, Coronation Street) and Darren Boyd (Case Sensitive, Dirk Gently) play the young couple living in hope that their son will one day be found. Five years on, Arcadian Gardens is a very different place. An address synonymous with tragedy. The grief-stricken parents and their neighbours lives were torn apart by the events of that weekend, not least that of Callum’s big brother, Luke. Then, on the eve of the fifth anniversary of his disappearance, Callum’s body is discovered, buried only yards from his own front door. And the nightmare begins all over again. DCI Maggie Brand leads the new investigation. Pregnant when Callum went missing, debilitating morning sickness had forced her to step down from the original investigation. Her son, Sam, was born only a few months after Callum disappeared. Now he’s starting school and Maggie has to deal with her own feelings of loss, as she confronts the reality that her little boy is very different to the other children in his class. Driven by her obsession to discover what happened to Callum, Maggie leaves no stone unturned in piecing together the events of that fateful night.