When Jack and his family arrive on the remote, blustery Scottish island of Morna, the whole summer holiday seems doomed – until they find the den. The three children who claim it are the only other children their age on the island – and soon Jack, Tressa and Milo are initiated into their secret society, the Binding, which charismatic Duncan presides over with elaborate rules, ceremonies and punishments. Jack wants to belong – he doesn’t want trouble. But as the summer goes on, he begins to understand more about the Binding. Jack’s going to have to stand up to Duncan – whatever it costs him.