A tightly plotted, gripping crime thriller which delves into complex moral issues. When extremists kidnap two seven-year-old boys from very different backgrounds, and promise to release them only if their radical demands are met, the case falls into the hands of intuitive and pragmatic Detective Superintendent Iain Barclay. Faced with an inexperienced and increasingly unreliable team, Barclay calls his friend and faithful deputy, Detective Sergeant Amy Foster, out of 'early retirement' - and away from the bottle - to support him in solving what turns out to be a highly sensitive crime. Emails arrive at Barclay's office, with images attached of the two boys seemingly unconscious, each with the word 'sacred' written on his body and a series of demands which the police team simply cannot meet. Barclay and Foster realise that if the boys are to survive, they must find the kidnappers quickly.