In Too Deep (The 39 Clues, Book 6)

In Book 6 of The 39 Clues series, fourteen-year-olds Amy and Dan travel to Australia in search of answers about their parents and the clues they seek. As they uncover hidden memories and navigate dangerous situations, they find their perceptions of friends and enemies tested, leading to unexpected and tragic consequences. Haunted by their past and pursued by rivals, the siblings must decipher who they can trust.