Walking through the misty Florida woods one morning, twelve-year-old Rob Horton is stunned to encounter a tiger-a real-life, very large tiger-pacing back and forth in a cage. What's more, on the same extraordinary day, he meets Sistine Bailey, a girl who shows her feelings as readily as Rob hides his. As they learn to trust each other, and ultimately, to be friends, Rob and Sistine prove that some things-like memories, and heartache, and tigers-can't be locked up forever.