They make eyes at each other in the Super Kmart. Out in the parking lot, he tells her about what he and his crew do for a living: “We explore America, we party, do a whole buncha shit. It’s cool.” He invites her to join them. Since the previous scene found her dumpster diving for dinner for herself, her younger siblings, and the father who molests her, she is not a tough sell.

Her name is Star (Sasha Lane), and she’s the central character in Andrea Arnold’s new dirtbag epic American Honey, which tells the story of how she goes on the road, finds a new family, sees the country (part of it, anyway), makes some money, gets into some trouble, and falls into something like love with the guy who recruited her. His name is Jake, and he’s played by Shia LaBeouf in a performance that explains a lot about his bizarre physical appearance last spring, when he was turning up at events with odd piercings and a rat tail hanging over his shoulder. Yet that look makes complete sense for the strange character he’s playing here, who’s all fast talk and confident moves – until the real ringleader shows up.

And her name is Krystal (Riley Keough), the sexpot mastermind of this little operation: she and her crew of late-teens roll into a new Midwestern town every week or so, hit the suburbs with pamplets and fundraising tales, and scrape together as much money as they can selling “magazine subscriptions,” which mostly serves to get their sticky fingers into rich people’s houses. That’s during the day; at night, they drink and smoke and fuck and fight (the film plays, as odd a mixture as it may be, like a cross between Glengarry Glen Ross and Spring Breakers). Little rumbles break out left and right, as though these aren’t young adults but attention-deficient children – which, in a way, they are. “We have fun,” Jake explains to Star, who is both freaked out and fascinated.

Most of the actors playing the sales crew don’t seem to be actors at all, which I mean as a compliment; it feels like Arnold might have herself gathered them from a Kmart parking lot. But their messy, half-overheard conversations and unforced interaction feed into the picture’s restless, boundless energy. Arnold also gets shots of vibrancy from music of all kinds – there’s as much in her film as in a literal musical, an almost constant stream of blasting radios and phone speakers, source music that becomes their soundtrack, and the film’s.

The music, in turn, informs the film’s wild, anything-goes storytelling spirit nicely. American Honey runs an expansive 163 minutes, and yes, it could be shorter. But the most memorable moments are frequently those that would’ve been the first to go from a trim, 100-minute version – awkward interactions and sticky situations that we keep waiting to go sideways, conversations that go long because they can, and are better for it.

Many of those are between Star and Jake, whose attraction gives the affably shambling narrative its spine. He uses their attraction to hook her, but it doesn’t take her long to realize he’s basically a kept man, at the service of confident Krystal. Yet Star’s subsequent lovesickness and jealousy isn’t a cliché, and not just because Arnold’s script and offhand style so handily capture the end-of-the-world nature of teenage love – we get why she falls for him, and for everything he represents. Jealousy and sexual gamesmanship (from both Jake and, eventually, Star) end up fueling their own desire, and the intensity and desperation of their fleeting stretches alone.

Lane is one of those performers who is so casual, it’s easy to take her for granted – you can’t catch her acting. That’s a good fit for LaBeouf, who’s probably better here than he’s ever been in a film; he’s so good, in fact, that it’s easier to write off his bonkers off-screen behavior over the past few years (and that’s not always the case). Whatever he’s doing now, it’s working – he’s never less than convincing, and that goes double for the movie. It feels, like Arnold’s work so often does, homemade, and I’m not sure whether they actually just popped a skeleton crew into a second van and followed the actors around the Midwest, but it feels like they did. I’m from that area, and the verisimilitude is striking – I’ve been in these extended stay hotels, these trailer homes, these highway rest areas, and American Honey gets the feel of those places, their rhythms, and the particular kind of sadness you can feel if you’re in them too long. And yet it also knows, just as forcefully, how easy it is to lift yourself up and away, if you’ve got the right combination of friends, and pop songs, and fireworks.

American Honey is out Friday.