Ben's mother has been kidnapped and the adults don't believe it. They think she's just missing and her employers and the police don't really want to know. The meeting she attended, after all, never took place. But the message she sent Ben tells a different story. To find his mum Ben must follow a perilous trail and solve a series of difficult clues, whilst evading being captured by the kidnappers. With help from his alarmingly clever cousins, Jess and Freddie, as well as some hindrance from his uncle, he investigates her mysterious disappearance. Tormented by conflicting leads and a growing threat, Ben's search becomes increasingly desperate. Can he solve the puzzles and save her, before anything terrible happens to her - or him?