Thirteen-year-old Max Tilt discovers the unfinished and unpublished manuscript of his great-great-great-grandfather Jules Verne, which reveals that everything he wrote was not fiction but fact. Together, Max and his cousin Alex set about finding the treasure in this last manuscript of Verne's, hoping it can save Max's mother and his home--but they have a rival in the strange man Spencer Niemand, who has spent his life working to unlock the clues in Verne's fiction.