As told in flashback by the participants themselves, Al (FREDDIE PRINZE, JR.) and Imogen (JULIA STILES) are young lovers for whom sparks immediately fly upon their first meeting when he's a sophomore and she a freshman at a New York college.
As their relationship intensifies, they must contend with the reactions of their friends to their romance, including that of Eddie (SHAWN HATOSY), Al's insecure roommate who'd like a girlfriend like Imogen, and Monk (ZAK ORTH), an underground porn actor and director, whose industry friend, Cyrus (SELMA BLAIR), finds herself attracted to Al.
Then there's Al's dad, Chef Ray (HENRY WINKLER), who likes Imogen but wants Al to join him in a father/son cooking show, as well as Imogen's friend, Lana (ROSARIO DAWSON) who has a brief fling with Eddie, and Jim Morrison (ASHTON KUTCHER), who looks like the former leader of The Doors and has a thing for Imogen.
With time passing and the sparks of their early romantic relationship eventually being replaced by a comfortable, but not particularly exciting steady relationship, Al and Imogen must contend with trying to adapt to their evolving and somewhat stagnating relationship.