Countdown (The 39 Clues: Unstoppable, Book 3)

In "Life or Death," thirteen-year-old Dan Cahill finds himself in a perilous situation as the leader of a powerful family, with he and his sister, Amy, constantly evading dangerous foes. As their luck runs out and Dan faces imminent danger, Amy must confront a chilling choice: to save her brother, she might have to unleash a dark force far more menacing than their enemies. This gripping tale explores the lengths a sister will go to protect her sibling amidst dire circumstances.