|Pages:||Varies by Book|
|Preceded By:||Cahills vs. Vespers|
Unstoppable is the series that will follow the Cahills vs. Vespers series. It will have four books. Publisher's Weekly said: "The new storyline sends protagonists Amy and Dan Cahill on even further-flung adventures as they explore the lost civilizations of the world."
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The 39 Clues is unstoppable! The bestselling series returns with an adventure spanning four explosive books and a website that places readers right in the action.
Amy and Dan explore the lost civilizations of the world in these books.
This book is curently being written by Jude Watson. It will be released October 1st, 2013.
The Cahill family has a secret. For five hundred years, they have guarded the 39 Clues — thirty-nine ingredients in a serum that transforms whomever takes it into the most powerful person on earth. If the serum got into the wrong hands, the disaster would rock the world. So certain Cahills have always made it their mission to keep the serum safe, buried, locked away. Until now.
Thirteen-year-old Dan Cahill and his older sister, Amy, are the latest guardians of the Clues. They think they've done everything right, but a tiny mistake leads to catastrophe. The serum is missing and Dan and Amy have to get it back and stop who stole it . . . before it's game over. For everyone.
This book will be written by Jeff Hirsch. It will be released in January 2014.
The series "finale" will be written by Gordon Korman. It will be released in August 2014.