Sammy is thirteen and lives with his mum in Tipton-on-Sea. His dream of deep sea scuba-diving is thwarted when his first lesson is brought to a halt by a commotion. A fishing boat has gone missing. Mrs. Anderson claims the boat has been stolen and she knows who did it putting the town's residents in complete shock - no such crime has been committed in living memory. Sammy and his scuba teacher, Mr Murphy, seem to be the only two who question Mrs Anderson's evidence but when they challenge her, they discover the town is turning on them for not trusting her. Can Sammy and Mr Murphy find the truth of the missing boat before their warm, friendly town is lost forever?