I’ve still got a bit of a warm glow from seeing Adventureland, the new offering from writer-director Greg Mottola. It’s a story that other creators may have been tempted to inflate into something bigger, but by staying with what I strongly suspect are his feelings if not the facts of what he did in the summer of 1987, Mottola has arrived at a charming coming-of-age story that works because of the sincerity of its script and performances.

James Brennan was hoping to travel in Europe before studying in New York, but his father’s demotion means that he has to find a job himself, and the only one available is in the lousy local themepark, Adventureland. The unamusement park is depicted just right, a moribund place that most attracts young people at a loose end in their lives, the exceptions being DIY man Mike, rumoured to have jammed with Lou Reed, and the avuncular owners of the attraction, whose number one rule is not to let any of the visitors leave with one of the few remaining big-ass panda teddies that are on display as prizes. Naturally, James finds himself in a situation where he is relieved of one of said pandas, though to be fair its redneck ‘winner’ is carrying a knife. Anyway, this unfortunate transaction introduces James to Em, who soon becomes his love interest.

And that’s kind of it. Don’t expect any road trips, encounters with mentors, complex set pieces, or much else than a credible and touching depiction of a relationship that causes pain for both James and Em. He’s a virgin, and unsure of much except that he loves Em. She’s involved with the married DIY dude, and it’s messing her up. Their inability to untangle all this and kindle the warmth between them into the heat of love is the melancholy path that this bittersweet movies treads perfectly.

What helps along the way is the surety that this is 1987 we’re experiencing. The musical choices are pitch-perfect, from Husker Du in Em’s car to the ghastly Rock Me Amadeus that one of the park rides blares out 20 times daily, a dismal metal band that plays in a local bar to the pain experienced by Em when an asshole drummer tries to impress her with his Rush impression because he’s heard she’s into musicians.

Maybe all this has particular resonance with me because I spent the summer of 1987 working and traveling in America myself, and know what it’s like to put a C90 of meaningful songs together for a girl you’re into. But plenty of films have covered this kind of territory before without convincing me…so what makes Adventureland work where others have failed?

Ultimately, the answer to that has to be naturalism. Adventureland has the reek of life about it, in the same way that Napoleon Dynamite has, and that a lot of other films overstyle one way or another. And that’s important about films that want to convince you about their protagonists, welcome you into their worlds. These are characters prone to the same kind of low-status humiliations that real teenagers struggle with in seeking to make their misshapen bodies do what they’re supposed to, and say things that represent their shifting beliefs and feelings while knowing that those utterances will put them in a pecking order, all the while subject to the whims of older people with more power than them, often for the most arbitrary reasons.

The one area where this lovely film failed to convince is in its coda, where James and Em meet in New York a while after their time in Adventureland, and consummate the relationship that they began there. It works in the sense of a well-turned third act, but here I suspect we’re seeing what Mottola wishes had happened rather than what actually did. Life has loose ends, and when we’re younger in particular there are all kinds of ‘what-ifs’ that never get resolved for real. I sort of wish that he’d had the courage to end the film at the melancholy point things reach at the end of the time in the theme park…but I can also recognise the impulse to give your younger self the break that you never actually experienced.