Tony Danza and Joseph Gordon-Levitt in Don Jon.

Joseph Gordon-Levitt writes, directs and stars in Don Jon, a frank comedy about a sex addict who thinks porn is better than true romance.

Levitt is excellent and consistently funny as the title character, a Jersey boy who is quite the stud, yet he finds himself jerking off to Internet porn within mere minutes of finishing with a live woman.

His little problem comes to the forefront when he meets Barbara (Scarlett Johansson), the first real love of his lifeโ€”a woman with high standards who doesnโ€™t approve of the porn thing.

The movie is full of porn clips, so donโ€™t see it with kids or a first dateโ€”unless you and that first date have some sort of naughty understanding.

Gordon-Levitt has given us something akin to a funnier Saturday Night Fever, with porn replacing disco. Julianne Moore is her usual excellent self in a supporting role, and the surprising casting of Tony Danza as Donโ€™s dad proves smart: Danza displays cinematic comedy chops that he hasnโ€™t been able to show off before.

This is a triumph for Gordon-Levitt. Go see it.

Don Jon is playing at theaters across the valley.