The Castle in the Sea: Quest of the Sunfish (Book 2) by Mardi McConnochie
Once more, Annalie, Will, Essie and Pod set out on the Sunfish to look for Spinner – their only clue a coded list Spinner left behind, naming four scientists who were once his colleagues on a top-secret project. When a terrible storm separates the crew and almost wrecks the boat, Will and Essie must use all their courage and ingenuity to try and make their way back to the others.
Meanwhile, Pod and Annalie, travelling in the crippled Sunfish, are captured by pirates, who agree to fix the Sunfish – at a price. Not all of Spinner’s former colleagues can be trusted. Worse still, their old nemesis Beckett is still on their trail. Can they follow the clues, track down the scientists, and find Spinner before Beckett does?
The second breathtaking adventure in the Quest of the Sunfish series.