The 39 Clues


  1. Mission Titanic
  2. Mission Hindenburg
  3. Mission Hurricane
  4. Mission Atomic
Book 2: Mission Hindenburg

The Cahills are the world's most powerful family, but their strength is being tested. A sinister man calling himself The Outcast has targeted the family and set them an impossible test. He's recreating four of history's worst disasters and challenging the young Cahills to find and stop the tragedies before it's too late. Now, with one disaster behind them, siblings Dan and Amy Cahill and their friends have just days to discover what the Outcast's next move will be.

Their frantic search seems to be pointing toward a terrifying air disaster, the explosion of the Hindenburg airship. But no one travels by airship anymore — what do the Outcast's cryptic messages mean? The young Cahills must split up and take to the skies to try to find the answer . . . before their whole world comes crashing down.

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C. Alexander London

C. Alexander London

C. Alexander London is a top Ekat agent and the author of many books including the Dog Tags series. When he’s not writing, he can usually be found walking around New York City talking to his dog . . . who may or may not also be a secret agent.

C. Alexander London

Other Books By C. Alexander:

  • Tides of War
  • The Wild Ones
C. Alexander London - Front C. Alexander London - Back

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The 39 Clues is a storytelling adventure that leaps across books, cards and this website to put YOU at the center of the action. You are a member of the Cahills, the world’s most powerful family. The source of the power has been hidden across the globe in the form of 39 Clues. In the first series, The Clue Hunt, your mission is to find the 39 Clues – at any cost. The series kicks off with Book 1: The Maze of Bones by Rick Riordan. The second series is Cahills vs. Vespers, which introduces you to a deadly enemy hiding in the shadows. Your mission is to stop the Vespers – before the world pays the price. Cahills vs. Vespers launches with Book 1: The Medusa Plot by Gordon Korman. Do you have what it takes?