As the title suggests, Jim (Biggs) has finally plucked up the courage to ask his perky girlfriend Michelle (Hannigan) to marry him. Now his friends Finch and Kevin (Thomas and Nicholas) are helping him get ready ... with a lot of interference from good-time boy Stifler (Scott), who gets even more involved after meeting Michelle's babe-a-licious sister (Jones). Meanwhile, Jim's dad (Levy) continues to offer far more advice than is strictly necessary, while Michelle's parents (Willard and Rush) stumble into every embarrassing situation imaginable.

This is a slicker, more realistic movie than Part 2--Herz's script is full of extremely witty comedy, even though director Dylan never cranks up enough energy to make them come to life. Much of the film falls flat, with stilted set pieces (the bachelor party farce doesn't work at all) and two too many syrupy musical montages.

It only works because the cast have settled into these characters comfortably--they are much funnier as people now, simply because there's more to them now. Sure, the stereotypes are still there, but at least they have some fun with them. Both Biggs and Hannigan go for a more mature performances--still funny, but much more interesting characters, even though poor Biggs spends most scenes with trousers around ankles. Scott (who's over-the-top as usual) and Thomas have fun swapping personalities to compete for a girl's affections. And Levy continues to be the only cast member with expert comic timing (the other pro, Willard, is virtually wasted).

There's also an intriguing layer of gay subtext that the filmmakers seem afraid to explore; endless innuendo, a camp new character (Kramer) and a hilarious sequence in a gay bar all hint at much more than the script seems willing to go with. Maybe next time....