Alisa has been chosen to work as a stunt double on horseback for a big adventure movie being shot in Colorado, along with her horse Diabolo. But the minute Alisa begins work, her co-rider, Sophie, seems to have it in for her. As things go from bad to worse on set, Stardust Stables is having problems of its own. Lizzie's ex has put in a claim for half of the Stardust horses, and Diabolo is on his list . .