Stuffed with familiar themes from coming-of-age classics like The Summer of 42, Ferris Bueller’s Day Off, and Moonrise Kingdom, The Way, Way Back is a long stretch from its predecessors, but the film is salvaged by a terrific cast.

Liam James as Duncan and AnnaSophia Robb as Susanna in “The Way, Way Back.”

By Glenn Rifkin

As the new coming-of-age comedy The Way, Way Back opens, we see a morose Duncan, the film’s 14-year-old protagonist, seated in, what else, the way way back of his mother’s creepy boyfriend’s station wagon. He’s in the seat that faces to the rear, in a none too subtle metaphor, and his glum expression lets us know that he would rather be anywhere but in this vehicle. Steve Carell, playing against type as Trent, the obnoxious, sleazy boyfriend, prods Duncan to answer the question, “On a scale of one to 10, what would you give yourself?” Duncan reluctantly gives himself a six. “I’d give you a three,” says Trent in a condescending manner that makes Duncan’s lip curl.

Thus begins the summer vacation at Trent’s Massachusetts beach house in which Duncan, with the help of a sage guru, discovers his coveted self-worth that confirms that he is far more than a three. Though filled with familiar themes and a long stretch from coming-of-age classics like The Summer of 42, Ferris Bueller’s Day Off, or Moonrise Kingdom, The Way, Way Back is salvaged by a terrific cast but most especially by the comedic stylings of Sam Rockwell, who plays Owen, the wise and wise-guy manager of the local water park who befriends Duncan and turns his nightmare summer into a wet but transcendent growth spurt.

In fact, if not for Rockwell, this film would be nearly comatose. With a script by Nat Faxon and Jim Rash, the pair who shared a 2012 Oscar for best screenplay with Alexander Payne for The Descendants, the movie sets up a classic adversarial relationship between Duncan and Trent, which does more to hold the movie down than make it soar. Yet again playing a stressed-out single mom trying to hold it all together, Toni Collette makes as much as she can from her thinly-written role as Duncan’s recently divorced mother. The brilliant Collette, whose “mother” resume includes The Sixth Sense, About a Boy, and Little Miss Sunshine, can’t decide whether to hang on to this increasingly creepy boyfriend or defend her adolescent son. This leaves Duncan to fend for himself and long for his absent father, who seems to have abandoned the lonely boy. The themes, as I said, are very familiar, and the script unfortunately takes little advantage of the skills of Collette, Allison Janney, as the alcoholic neighbor, or Maya Rudolph, as Rockwell’s water park girlfriend.

A family gathering in “The Way, Way Back.”

In this case, Faxon and Rash directed as well as wrote the screenplay, and both appear in key comedic roles as staff at the water park. Filmed last summer in Wareham, The Way, Way Back will feel familiar to Massachusetts folks who summer at the South Shore. What will feel downright exhilarating is Rockwell’s breakout performance as Owen, the manic, quick-witted slacker, who sees a lot of himself in Duncan and hires him to work at the water park. Pretty much every explosive laugh line in the script goes to Rockwell, who usually portrays psychopaths (The Green Mile) or straight dramatic roles (Moon). Here, he brings to mind the hyper styling’s of Michael Keaton in Night Shift and Beetlejuice. The one-liners fly so fast that the audience laughs over many of the equally funny follow-ups. The talented Rockwell manages to infuse his humor with a sweet empathy that avoids cliché, and in so doing, he carries the film as far as it can go.

The marvelous Janney has her moments, specifically in an early sequence in which she tries to foist her young son Peter on Duncan and relentlessly riffs on Peter’s wayward lazy eye. It is cruelly hysterical, and the resigned Peter strides off sighing, “You are the worst parent.” In fact, the adults in this movie are persistently more adolescent and incorrigible than the youngsters. Their behavior and conversation in front of the children is uncomfortably inappropriate: part of the takeaway is that it is foolish to underestimate the insight and wisdom of the kids in a world populated by dysfunctional grown-up buffoons.

Liam James does a passable job as Duncan, but during the film’s climactic backyard barbecue confrontation with Trent, James manages just a single when a home run was needed. Still, The Way, Way Back is enough of a feel-good distraction to be welcomed in a summer season of zombies, dispiriting sequels, and apocalyptic drivel.

Glenn Rifkin is a veteran journalist and author who has covered business for many publications including The New York Times for nearly 30 years. He has written about music, film, theater, food and books for The Arts Fuse. His new book Future Forward: Leadership Lessons from Patrick McGovern, the Visionary Who Circled the Globe and Built a Technology Media Empire was recently published by McGraw-Hill.