Into the Gauntlet is the tenth book in The 39 Clues novel series. It was written by Margaret Peterson Haddix and released on August 31, 2010. In the beginning of the book, Amy and Dan are now at the end of there clue hunt, and every misfortune they've had. Their lead is a poem found in their hotel room. However, it is then stolen by Isabel Kabra. It is revealed that William Shakespeare was a powerful Madrigal and the most important clue is on the line against their competitors. Dan and Amy are supposed to go to the Globe theater to watch a Shakespeare play, Romeo and Julliet. While watching the show they see what looks to be ninjas. The ninjas find a clue at the top of the theater but drop it into the hands of Dan and Amy. As it turns out the whole Cahill family is at the play looking for