Credit: Abbot Genser

For anyone making a youth nostalgia film, it’s easy enough to nail the signifiers: the clothes and the cars, the great songs (or kitsch classics), the ”casual” references to famous news events. What’s harder to catch is the mood, the vibe, the aspects of an era we didn’t even know were defining until the movie revealed them. Greg ? Mottola’s Adventureland is set in Pennsylvania in 1987, and in form it’s a sweetly traditional how-I-spent-my-summer-vacation romantic comedy, with Jesse Eisenberg as James Brennan, a sharp-witted, nervously sincere young man who fills up the months before he enters Columbia graduate school by working at a run-down amusement park. The place is called Adventureland (it’s anything but), and once James is ensconced there, he hangs out all day long, listening to endless replays of ”Rock Me Amadeus” as he hands out stuffed animals to lucky prizewinners and gets to know the other kids who are toiling away at this seedy wage-slave carnival. The jobs are crap, but they’re all in it together, and they become friends.

So far, so conventional, except that Mottola, the director of Superbad, works with rare feeling and flow. He shows every bit as loving and pinpoint-perfect an observational eye for the late ’80s as George Lucas did for the end of the greaser era in American Graffiti and Richard Linklater did for the free-ride ’70s in Dazed and Confused. The movie looks as if it was shot in the Reagan era, with a darkly grubby low-tech surface, and part of its ? gentle magic is that Mottola knows how to bury his period references deep inside the attitudes that first enveloped them. The playing of once-nifty, now-ancient videogames is accompanied by much mock wow! chatter at their battlestar awesomeness, and when the park’s resident hottie, the swaggering Lisa P. ?(Margarita Levieva), shows up, we can see that she’s modeled her entire look and boy-toy ‘tude on Madonna, yet the pop star herself is never mentioned. Joel (Martin Starr), the morosely ironic literate loser of the bunch, would have been the purest of nerds in an earlier era, only now he’s an indie nerd who tries to be a bit cool by declaring how uncool he is, and by smoking a pipe.

The ’80s, at least at the time, ?appeared drenched in irony, in the jadedness of a generation whose members, schooled on John Hughes and MTV, had grown compulsive about status and image and occupying their prescribed roles. It’s Mottola’s funny and touching inspiration to look back and see how unself-conscious the decade now seems, from the vantage of the ”Whatever!”/Twitter era. The characters don’t even hook up — they make out. And talk about making out. How innocent can you get?

Eisenberg, all grown up from The Squid and the Whale, is gangly and handsome now, but he plays James with his head slumped like a turtle (to let us know the guy doesn’t realize that he’s attractive), and with a percussive, head-shaking stammer that still has a note of Woody Allen in it. James is a virgin, chivalrous to a fault, and too sincere for his own good — which is what’s desperate about him, and winning, too. He’s still trying to figure out what his own role is. Whereas Em (Kristen Stewart), the flashing-eyed girl he befriends and starts to date (sort of), is all too good at projecting an image. She knows how to hide her troubles, of which she has plenty. Stewart, as she proved in Twilight, has a cutting sharpness that draws you right to her pale, severe beauty. She makes Em just the kind of good-bad girl a lamb like James needs to set himself free.

There are many stray pleasures in ? Adventureland, from Bill Hader’s hilarious turn as the dumb cluck who runs the park to Ryan Reynolds’ seen-it-all cool as the mechanic and resident stud who’s a lot more vulnerable than he looks. And when it comes to those soundtrack gems, Mottola has perfect pitch: He makes splendid use of Crowded House’s ”Don’t Dream It’s Over” for its melancholy rapture, Shannon’s ”Let the Music Play” for its exhilarating throb and crunch, and a dozen others that will have you wistful for melodies you may not have even loved at the time. That said, there’s a slightly predictable mildness to the movie’s storytelling. Adventureland doesn’t quite soar?it lopes along affectionately. But for nostalgia junkies, it’s one from the heart. A?