The Way, Way Back Liam James, Sam Rockwell, Steve Carell, Toni Collette. Directed by Nat Faxon and Jim Rash. Rated PG-13. Opens Friday.

If you want to make an ’80s movie, maybe you should just set your movie in the ’80s. The Way, Way Back so closely evokes the coming-of-age summer movies of the 1980s (complete with a throwback-style water park, a sing-along to REO Speedwagon, a vintage station wagon and a near-total absence of modern technology) that it’s baffling why writer-directors Nat Faxon and Jim Rash didn’t just set the movie in 1986. That might have added a bit of authenticity to what comes across as a completely superficial and contrived story without an ounce of genuine emotion.

Faxon and Rash (who are better known as actors) won an Oscar for co-writing Alexander Payne’s The Descendants, but they lack Payne’s visual creativity and way with actors. The cast is packed with familiar faces (Steve Carell, Toni Collette, Allison Janney, Maya Rudolph, Amanda Peet, Rob Corddry) whose talents are wasted on one-dimensional or overly broad characters. The star, however, is non-familiar face Liam James, playing Duncan, a sullen 14-year-old forced to spend the summer in a generic beach town with his mother (Collette) and her douchebag boyfriend (Carell).

Duncan develops a crush on his neighbor (AnnaSophia Robb) and finds a kindred spirit in Owen (Sam Rockwell), the slacker proprietor of the aforementioned old-school water park. Rockwell gives the movie’s liveliest performance as a character who uses sarcasm to hide his deep regrets, but that just means he has two dimensions instead of everyone else’s one. Faxon and Rash mimic the rhythms of entertaining and affecting coming-of-age dramedies without capturing the feeling, and when Duncan rides away from his vacation home at the end of the movie, there’s no sense that he’s changed or grown or done anything other than meander from scene to scene.

Part of that is because James never quite projects any of Duncan’s inner emotions, but it’s mostly because the script doesn’t give him much to project, and Faxon and Rash use montages set to plaintive indie rock in place of actual character building. There are some funny moments in The Way, Way Back, but when it comes time to reach the audience in an honest, heartfelt way, the movie falls short.