Watch Free Online HD Moviesjoy. "120 beats per minute—at this tempo, twice as fast as the human heartbeat, disco music gets the blood pumping and revs up the libido. In the 1970s, when eroticism took over the silver screen and sex ceased to be a purely private matter, disco became the soundtrack of the sexual revolution. A film about the surprising connections between disco and pornography—and how erotic content increasingly found its way into pop culture.