Storm Warning (Park novel)

Plot

While leaving China, Amy and Dan receive a call from the Holts, who claim to know their destination. The siblings suspect that Nellie Gomez, their au pair, informed the Holts. On the plane, they persuade Nellie to share information, learning that Grace, not Beatrice, hired her. Nellie also admits to working for Mr. McIntyre but does not reveal her true employer.

Amy and Dan grow distrustful and try to avoid her. In the Caribbean, the clue hunt results in the death of a non-Cahill named Lester. Shocked and angry, Amy and Dan decide to confront Aunt Beatrice, but Nellie kidnaps them and takes them to Moore Town to meet The Man In Black. There, they are forced to solve a puzzle box found in Lester's museum, using items representing the branches: a jade with a dragon, a bear claw, a wolf tooth from Isabel Kabra's bracelet, and Nellie's snake-shaped nose ring.

Solving Anne Bonny's puzzle box yields the Madrigal clue of Mace and the direction to go to England. Amy and Dan learn that The Man In Black, who had followed them in earlier books, is Fiske Cahill, Grace's brother, who ran away as a child.