When a crazed elderly man and his sister begin firing bullets from their balcony down onto the Vigata street below, Inspector Montalbano finds himself a reluctant television hero. A few days later, when a letter arrives containing a mysterious riddle, the Inspector becomes drawn into a treasure hunt set by an anonymous challenger. He follows the clues, travelling from Vigata's teeming streets to its deserted outskirts. But when a horrifying crime is committed, the game must surely be laid aside. And it isn't long before Montalbano himself will be in terrible danger ...