How do you make a movie that tackles pornography not just as an ''issue'' or a product but in terms of its psychological effects? Joseph Gordon-Levitt, the writer, director, and star of Don Jon, has done it. And he's pulled it off in a light, fun, unlaborious way: by crafting a high-spirited yet dirty-minded romantic comedy about a New Jersey bartender, Jon Martello (Gordon-Levitt), who goes out to clubs and gets laid every weekend, usually with the curvaceous babe of his choice. She can never be the woman of his dreams, though, because those dreams have already been lost to the hardcore photographs and videos that he masturbates to every day. It's not really the faces and bodies he's coveting, it's the behavior the moaning, screaming, make me your nasty toy insatiability, which he thinks is what sex was meant to be. He doesn't realize that he's watching a bill of goods made flesh.
As Jon, Gordon-Levitt sports a buffed-up chest and hair greased into a stylish oil slick, and he speaks in low, flat tones, giving a witty turn as a studly ''Guido'' who digs his life of anonymous sex and control; he's like The Situation without the fame or preening smarm. One night out at the club with his wingmen Bobby (Rob Brown) and Danny (Jeremy Luke), Jon spies Barbara (Scarlett Johansson), as gorgeous a woman as he's ever seen. He wants to get with her, and before long they're an item. But then the disappointment sets in. In his mind, his heart, she can't compete with the extreme libidos of the porn world. It doesn't help that she's an ''addict'' too, hooked on rom-coms and their fantasy of a man who'll cater to her every whim.
Gordon-Levitt proves a natural filmmaker, nimbly staging Jon's highly amusing Catholic confessions, along with porn montages that mimic the dopamine-charged editing of Requiem for a Dream. He also gets a terrific performance out of Tony Danza as Jon's hilariously blinkered brute of a dad. The bond between Jon and Esther (Julianne Moore), the troubled older woman he meets in an adult-ed class, isn't as deftly drawn. She's there to teach Jon lessons, and does. But Gordon-Levitt's intuitive performance makes even this part of the film work. Jon is a guy who needs to quit his porn addiction, but to do that, he must understand that what he's really been having is a dysfunctional relationship with porn. It's the mistress he's devoted to and has to break up with if he wants to start living. B+