It’s somewhat crudely made, and it hammers its main points. But at its best, “Mean Creek” has a whiff of the seriousness of 1970s American movies, when bad things happened and the hero didn’t always emerge victorious.

Oddly enough, it’s the second film in as many weeks that recalls “Deliverance,” which was one of those serious ’70s movies. Last week’s was the entirely frivolous “Without a Paddle,” of course, which isn’t quite the same thing.

The setting is a small town in Oregon, where the eternal drama of bullies, nerds and cool kids is playing out for the umpteenth time.

The bully here is a little different than usual. His name is George (Joshua Peck) and he’s an overweight, pompous techno-geek. As though to make up for his social maladjustment, he beats up on smaller kids like 14-year-old Sam (Rory Culkin).

Sam and his older brother Rocky (Trevor Morgan) confer with the designated James Dean of the town, the cool, angry Marty (Scott Mechlowicz). They cook up a mean bit of revenge.

They invite George along for a “birthday party” for Sam. Once they’re all in a big rowboat on the river, they’ll humiliate George and split.

When the day comes, the conspirators are joined by sensitive pal Clyde (Ryan Kelley) and Sam’s possible girlfriend Millie (Carly Schroeder). When Millie gets wind of the prank, she begs Sam to call it off.

But director Jacob Aaron Estes has already set the crew down the river, and at that point, it’s hard to alter the dangerous trajectory set in motion.

At times, this situation comes to chilling life. The kids play a game of “Truth or Dare” that has a really honest, unpredictable edge to it. The performances are exceptionally good for a young cast, with Estes getting a naturalness that aids his this-is-really-happening feel.

The diminutive Rory Culkin, who played Mel Gibson’s son in “Signs,” is closer in talent to his brother Kieran than to Macaulay, thank goodness. He does the thoughtful adolescent routine very well.

The other standout is Scott Mechlowicz, who played one of the leads in “Euro Trip” earlier this year. He gives a completely different performance here, and looks suspiciously like a star in the making. Or at least like the next Josh Hartnett.

“Mean Creek” struck me as pasting a grown-up level of gravity onto these teenagers for the purposes of the story’s heaviness. It’s not quite believable, and ultimately the movie seemed less impressive than a kids-in-peril picture such as “River’s Edge,” which it resembles.

It made an impression at this year’s Sundance Film Festival, but they’re always generous with out-of-nowhere films that show any grit. Call it a solid effort, and look for good things in the future from the cast.

“Mean Creek” HH

Well-acted: In a small Oregon town, a group of adolescents gets into trouble while going down a river and playing a prank on a school bully. The kids have a little more gravity than they should realistically possess, but the film is well acted.

Rated: R rating is for violence, language.

Now showing: tk

“Mean Creek” HH

Well-acted: In a small Oregon town, a group of adolescents gets into trouble while going down a river and playing a prank on a school bully. The kids have a little more gravity than they should realistically possess, but the film is well acted.

Rated: R rating is for violence, language.

Now showing: Harvard Exit.

From Page 6

Mean