Campbell Scott plays Roger, copywriter for an advertising firm in New York. He and his boss, Joyce (Isabella Rossellini) are in a physical relationship that ends, just as soon as Roger's nephew Nick (played by Jesse Eisenberg) comes to town on a "find out your ideal profession day" for his high school.
Nick knows Roger has a reputation for being a ladies man and asks him for advice on fishing for women. Over the evening Nick finds that Roger's reputation exceeds his record.
Roger is an atheist with a penchant for evolutionary psychology, and the movie brings up serious questions as to whether a life lived in the city with purely biological and sensual aims (Roger tells Nick at one point "sex is everywhere!" and his coworkers during lunch that men are using their primary utility to technological advances) can bring any kind of serious fulfillment. As you ask these questions you see Roger embarrass himself at the office party held by his boss (who by now has reeled in one of Roger's coworkers) and regress to a late night visit to a filthy whorehouse -- the "fail safe" option where women are always available -- with his 15 year old nephew.
Scott, Eisenberg and Rossellini perform spectacularly. Roger Dodger is able to be hilariously funny while asking serious questions, and is one of the best films I have seen in a long, long time. Most highly recommended.