When the old gypsy fortune-teller reads Captain Haddock's palm, she foresees trouble at Marlinspike Hall. Indeed, Tintin, Snowy and the Captain are scarcely home again before misfortune strikes. An accident, an unexpected visitor, an invasion by press and television, and then a robbery. Bianca Castafiore's emerald disappears. All of Tintin's skills are needed to reveal the identify of a strange and ingenious thief.