The “American Pie” gang returns in “American Reunion.”

In some ways, it doesn’t seem as though they have been gone so long. In others, it feels like they’ve been gone a very long time.

Thirteen years ago, they were high school seniors. They returned in two sequels, and at least one cast member returned in four more direct-to-video offerings.

When the first movie came out in the summer of 1999, it was a refreshing, irreverent new brand of comedy. Nowadays, it seems a bit too ... nice.

Except, that is, for Seann William Scott as Steve Stifler. He’s still the same jerk, and the only funny thing in this new movie, in which Jim (Jason Biggs), Oz (Chris Klein), Kevin (Thomas Ian Nicholas) and Finch (Eddie Kaye Thomas) gather together for the big reunion weekend.

All are having troubles in their relationships or in their jobs — except Stifler. He has no girlfriend, and he hates his job, although he has no qualms about insulting the boss.

Arriving back home, each guy is tested as old flames are ignited. Jim, who is married to Michelle (Alyson Hannigan) and has a baby, gets attention from a hot teen (Ali Cobrin) he used to baby-sit.

 Mena Suvari, Tara Reid and Dania Ramirez (the last a newcomer to the series) co-star as the girls that stir the other boys’ hearts.

As the reunion festivities start, the movie’s jokes all stem from the characters, especially Biggs’ Jim, getting caught doing something embarrassing — exactly on cue, never surprising or shocking. This stuff is just not funny anymore, if it ever was.

Meanwhile, poor Oz, Kevin and Finch rarely get even that much to do.

The film’s only humorous parts feature Stifler, who, unlike his friends, never navel-gazes, whines or worries about his troubles. He simply barges into a scene and takes what he wants. His brand of carnal honesty still works; he provides release in an age when worrying is no longer funny.

Unfortunately, even Stifler is given a so-called character arc, and is required to be unfunny for a large portion of the film’s second half.

In one of the best scenes, the pals suddenly realize that if they ever had any fun at all, it was because of Stifler.

The same goes for this movie.

MOVIE REVIEW

American Reunion ★★

Starring Jason Biggs, Alyson Hannigan, Seann William Scott, Thomas Ian Nicholas, Chris Klein, Eddie Kaye Thomas

Written and directed by Jon Hurwitz, Hayden Schlossberg

Rated R

Running time 1 hour 53 minutes