John Young is a depressed cop and recovering alchoholic, floating through life and suspicious that his partner and girlriend are having an affair. Among his assignments is the case of Barry Greene, an amateur pornographer and creator of the "Skin Horse" videos featuring sexual encounters between strangers. As his partner pursues the traditional leads, John follows his instincts. Led by Harlan, a nighclub owner and definitive collector of Green's oevre, John delves deeper into a seedy sexual underworld, eventually succumbing to his desire for one of his suspects.