Lee Raven, boy thief, has stolen something he really didn't mean to. Now he faces a perilous flight through London (and the murky sewers below) as he tries to escape capture - because Lee has stolen the Book of Nebo, a book that has existed for thousands of years and tells every story and legend known to man.

Washed ashore as a baby in ancient Greece, Halo is discovered by a family of centaurs. Although her true identity remains a mystery, she is loved as one of their own. But when Halo is dragged away by fishermen, her wild adventure begins.