The people behind the "American Pie" franchise seem to be genuinely under the impression that in the course of two gross-out movies audiences looking for lowbrow laughs have actually come to care for the series' one-dimensional characters.

Despite the fact that these comedies have been built almost entirely around boorish body fluid jokes and a very few bawdy gems ("This one time, at band camp..."), in "American Wedding" director Jesse Dylan jumps so impetuously from dog-doo-mistaken-for-chocolate gags to trite tender-moment montage sequences to sex scenes involving invalid grandmothers that none of it -- the jokes or the sentiment -- comes across with any conviction.

The plot of this third "Pie" movie revolves around the Murphy's-Law-plagued pre-nuptials of nervous nerd Jim (Jason Biggs) -- whose pastry-inclined self-gratification gave the first movie its title -- and flaky, sweet, secretly kinky geek Michelle (Alyson Hannigan), who fell in love with each other's sexual deviancies in "American Pie 2."

Showing little creativity in its stock comedy framework of embarrassing in-law misunderstandings, bachelor party strippers and the seduction of bridesmaids by chauvinist pigs, "Wedding" does manage to eke out a handful of out-loud laughs. Unfortunately, nothing that follows is as hilarious as the opening scene, in which Michelle mistakes Jim's fumbling proposal of marriage at a fancy restaurant as a sexual proposition. She crawls under the table to, errr, pleasure him, just as his dad (Eugene Levy) rushes in bringing the ring, which Jim had left at home. Not seeing Michelle anywhere, he sits down for a heart-to-heart with his son, and it escalates from there.

But even before this embarrassing moment has a chance to earn its first snicker, the filmmakers demonstrate how low their standards really are with the laziest kind of expository dialogue: "Well we did it. We graduated," says Jim to summarize what's happened since the last "Pie" movie. "You know, we've been going out for three years now..."

Spending 70 percent of its time setting up its jokes, half of which miss the mark, the script leans heavily on its extreme versions of "wacky" sitcom characters, notably the repellent, rage-aholic "American Pie" staple Steve Stifler. Played by Seann William Scott -- whose idea of acting is to hold one screwed-up, loutish, stoner-dude sneer for the length of whatever movie he's in -- Stifler is a one-note, loud-mouthed, sexist oaf. But that doesn't stop director Dylan ("How High") and writer Adam Herz (the creator of these "Pie" movies) from attempting to garner actual audience sympathy for him when he realizes he may have ruined his friends' wedding, thereby blowing his chance to bed Michelle's little sister Candice (January Jones).

(Demonstrating Herz's disregard for common sense as well, the sister and parents have come from "out of state" for the wedding, which is why no one has met them before -- so how is it that Michelle, Jim and Stifler all went to high school together?)

The only other returning cast members of note are Thomas Ian Nicholas and Eddie Kaye Thomas as Jim's buddies Kevin and Finch, but only Finch has any kind of storyline. In competition for Candice's affections, when Stifler tries to pass himself off as a preppy gentleman, the normally demure Finch turns vulgar and almost gets the girl. (Ultimately he ends up with Stifler's mom again, in one of the series' running gags.)

Built around the notion that anything outrageous is funny, the makers of "American Wedding" bank on the idea that easy teen- and college-age audiences won't care about tediously underwritten characters, a general lameness of humor and flaccid attempts at emotional investment (Jim takes Michelle on a romantic walk on the beach) as long as those audiences leave the theater with one or two over-the-top howlers to talk about.

They're probably right. But as with the first two "American Pie" flicks, this is the kind of movie you see again 10 years later and wonder why you liked it back when you were young and dumb.