The summer after Andi Carter turns nine the circus comes to town. She can't wait to get in line to see the elephants, acrobats, and--most of all--the champion bareback rider. What could be more thrilling than riding your very own horse under the big top?

When the Carters see the show, Andi meets Henry Jackson, a small boy selling concessions. Andi thinks his job must be perfect, hanging out with happy clowns, exotic animals, and excited visitors. But it's not all fun and games. Henry shares a secret with Andi: he ran away from home to join the circus--and now he's trapped. Andi wants to help him get free. But helping him may mean losing something very special to her.