When 22-year-old Chris finds himself in debt to a drug lord, he hires a hit man to dispatch his mother, whose $50,000 life insurance policy benefits his sister Dottie. Chris finds Joe Cooper, a creepy, crazy Dallas cop who moonlights as a contract killer. When Chris can't pay Joe upfront, Joe sets his sight on Dottie as collateral for the job. The contract killer and his hostage develop an unusual bond. Like from a modern-day, twisted fairy tale, "Killer Joe" Cooper becomes the prince to Dottie's Cinderella.