Twelve-year-old Rosemary has been an artist her whole life and especially loves drawing the incredible places from her Aunt Jo's stories. But illustrating the stories doesn't mean Rose believes them. And when Aunt Jo gives Rose a pocket watch with instructions on how to use it to access magical dream worlds, Rose just thinks Aunt Jo is being peculiar again.

While Rose is sleeping, however, she enters a fantastical place where each hour of the pocket watch takes her to a different world. There, Rose befriends a trio of outcasts with special powers and joins their war against the ominous Tall Man.

When a bully steals Rose's watch, she can only look on in horror as dream and reality collide and he's sucked into the Eleventh Hour. Now, Rosemary must gather magic from all twelve dream worlds to rescue the boy who makes her life a living nightmare.