Other than the trailer park left to her by her deceased daddy, Amy's favorite treasure is Jagger, her 180-pound bull mastiff. One day while she is away, Clayton, her best friend’s scumbag boyfriend sneaks into her yard and takes the dog. His prize fighting pit bull was killed during its last match, costing a lot of bad people a lot of money. To make up for his dog's losses, and to save his own life, Clayton enlists the help of a medical student dropout to turn Jagger into a killing machine by pumping him full of experimental drugs and muscle enhancers. Now Jagger is a monster, a beast that can't feel pain, with an unquenchable thirst for blood. He quickly breaks out of his pen and starts making his way home, tearing apart anyone in his path on his way to the one he feels has betrayed him the most—Amy.
