It used to be the Thirteen-Story Treehouse, but now Andy and Terry, two creative boys who write books together, have added on and it is Twenty-Six Stories now, complete with a skate ramp, the Maze of Doom, an ice cream parlor, and even an antigravity chamber--plenty of space to have adventures in.

As Isabel, the best bunjitsu artist in her class, continues to practice her skills, she also grows in her understanding of how to use her strongest weapon--her mind.