Joseph Gordon-Levitt is certainly no stranger to Sundance. He's been in Park City through the years to support star turns in films like (500) Days of SummerBrick and Mysterious Skin, as well as promoting his own social network/collaborative production company hitRECord.

Don Jon's Addiction, though, marks the young star's first feature-directing effort, and he also wrote and stars in this story of a Jersey Shore-style mook with a serious "addiction" to pornography, despite the suave guy's ability to constantly pull "10s" at the club.

That includes one Scarlett Johansson as Barbara Sugarman, who manages to wrangle Gordon-Levitt's character, Jon Martello, into a genuine relationship. I suppose if we're going to show a so-called "addiction" to pornography, it doesn't hurt to have a woman like Johansson on hand to illustrate just how driven Jon is to enjoy his online activities.

Gordon-Levitt proves a more-than-capable director, blending rapid-fire cuts to Jon's favorite Web sites, hilarious scenes at his family's dinner table (Tony Danza is excellent as Jon's dad) and a little romance into a nicely paced narrative that, in turns, is funny, touching, even disturbing. Watching Jon and Barbara interact provides some great laughs--often at the expense of New Jersey stereotypes. But when Julianne Moore enters the fray as a fellow student/recent widow in an adult-education class Jon's taking, and immediately spots Jon as more than what we see on the surface, the film takes a sweet, unexpected turn.

Jon's "addiction" isn't treated lightly, exactly, but his porn-cruising sessions are largely played for laughs--until Barbara finds out. And Moore's arrival as a woman with the experience to explain why Jon's seemingly innocent obsession is keeping him from satisfying real-world relationships offers a better anti-porn argument than anything any self-described moralist could come up with.

The performances are roundly excellent, from the leads to smaller characters like Jon's sister and club-hopping buddies. Gordon-Levitt's attention to detail, from Jon's apartment, to his family's offbeat dynamics, to the scenes at the club, is truly impressive.

If Don Jon's Addiction is indicative of what Gordon-Levitt has to offer as a film auteur in the future, we're all in store for some exciting work.

Remaining showings:

Jan. 21, 6 p.m., Sundance Resort

Jan. 22, 2:30 p.m., Library Center, Park City

Jan. 26, 12:15 p.m., Eccles Theatre, Park City