Scenario: You're standing at the bottom of a rock face. They've saved the most difficult extreme sport till last. Rock climbing is a massive challenge for your body and your mind. Can you make it to the top? Welcome to the Xtreme World of Billy Kool.Thrill-packed new series from the author of the best-selling Toocool books! In the new Xtreme series, the adventure moves from the backyard to an extreme sports television program. Each book in the series features a different extreme sport. Readers will be hooked from the word GO!