The 39 Clues: Doublecross Series is the 4th story arc in the 39 Clues Franchise, sequel to Unstoppable Series. It features 4 exciting adventure books for young adult readers, published between 2015 and 2016. The books are written by four different authors and among them, only Jude Watson has previously written books in the series. For the other three authors (C. Alexander London, Jenny Goebel, and Sarwat Chadda), their books are their first in the 39 Clues series.
The 39 Clues: Doublecross is the 4th story arc in the 39 Clues franchise, sequel to Unstoppable. The young-adult series starts brilliantly with the first adventure novel Mission Titanic. The book is written by Jude Watson and first published in 2015.
The 39 Clues: Unstoppable Series is the third story arc in the bestselling young adult franchise The 39 Clues. It expands the story of Amy and Dan Cahill after the first two series The Clue Hunt and Cahills vs. Vespers. The series features 4 adventure books written by bestseller authors including Jude Watson and Gordon Korman.
First released in October 2013, Nowhere to Run is a thrilling young-adult novel written by Jude Watson. It is the first book in The 39 Clues: Unstoppable series, the 3rd story arc in The 39 Clues adventure franchise, sequel to Cahills vs. Vespers series.
The 39 Clues: Cahills vs Vespers Series is the second story arc in The 39 Clues franchise, sequel to the original series (The Clue Hunt). This fantastic young-adult series features 6 adventure books written by bestseller authors—most of the authors also wrote the novels in the original series.
Originally published in 2011, A King’s Ransom is the second book in the bestselling young adult series The 39 Clues: Cahills vs. Vespers. The exciting adventure novel is written by Jude Watson. Dan and Amy Cahill have to go in dangerous quests once again. The Vespers has kidnapped some members of Cahill family and to get the hostages back, Dan and Amy have to do The Vespers’ dirty works.