Emmy, a fourteen year old girl who specializes in training Mustangs, the gorgeous wild horses that roam our plains. Emmy's training can gentle any equine, from client horses that pay the bills to her Extreme Mustang Makeover horses. This year, she’s more excited than ever about training her Mustang alongside two of her best friends. But this Mustang proves to be more dangerous than some of hers before...and Emmy doesn’t know if she can handle it. Throw in Emmy's crush, a herd of mysterious mustangs, her family and friends, and her odd neighbor, and things are bound to get interesting!