When Roo Thorn's beloved dad passes away, she doesn't expect to inherit much. Their unconventional life wasn't a wealthy one. But then she finds a winning lottery ticket in his coat pocket. Suddenly, Roo can have anything she wants - except her dad. And then she reads a letter from him, telling her to enjoy any money he's left her, to 'grab life by the wings and fly.' Roo makes a quick decision: she's going to buy what she's always wanted, a prize racehorse named Wonder Boy. When she arrives at Wonderboy's stables, the horse is everything she had dreamed of. Until he is stolen, from right underneath their noses, leaving no clues, no trail and Roo's dream in tatters. But if Roo's dad taught her anything, it's to keep dreaming, and so she and her aunt set off in their camper van, on a mad dash around the country, as more prize horses are stolen and the need to rescue them gets greater and greater.