The year is 1912 and with the success of Papa's latest baseball film, 13-year-old Rosie and her family move to beautiful Los Angeles to shoot more films starring Rosie. Within days of unpacking, Papa brings home an entire Wild West show so he can make authentic Westerns. Rosie's so excited about riding a horse for the first time that she forgets to watch her step-and before she knows it, she's caused a terrible accident for the show's best trick rider.