Having white supremacist skinheads as the villains in a horror movie seems like such an obvious idea, I’m surprised I haven’t seen it done before. (And before you scream Surf Nazis Must Die, stop. That was a comedy; it doesn’t count.) But Green Room takes the idea and runs with it, giving us a movie whose most horrifying concept is that these days, it doesn’t seem that far fetched.

East coast punk band The Ain’t Rights, (Anton Yelchin, Alia Shawkat, Joe Cole, and Callum Turner), are touring the Pacific North West in a beat-up van that often serves as their sleeping quarters, and runs on the gas siphoned out of parked cars. When a promised gig doesn’t yield the hoped-for payout, a local punk they do an interview with tells the band he can get them a gig at a cousin’s skinhead club, (“It’s right wing…well, technically far left”), and as long as they stick to their early “harder” stuff, the band should be fine.

The club turns out to be in a warehouse deep in the woods, filled with confederate flags, shaved heads, and Chelsea haircuts. Not exactly enamored with the setting, the band opens with the Dead Kennedys’ "Nazi Punks Fuck Off," and while the crowd’s response involves bottle tossing and spitting, it’s actually not much different from a positive reaction. The band makes it through the set alive, but on their way out, they stumble upon a murder in their green room, and find themselves trapped behind a locked door with some hostile skinheads and one possible ally (Imogen Poots).

What looks like it could possibly be another torture porn type horror movie—kids locked in a room, getting picked off one by one—is instead much closer to a siege movie, with shades of Assault on Precinct 13, as the heroes have to figure out how to escape their seemingly inescapable situation, some meeting grisly ends, and some using their wits to survive.

Director Jeremy Saulnier was part of the hardcore scene near Washington D.C., (and if you doubt it, he'll tell you all about it; a lot), and there's no doubt his experience adds definite realism to the club and its denizens. You can almost smell the stale beer and intolerance.

What’s perhaps most interesting about Green Room is that the villains, while irrevocably bad, aren’t faceless or mindless killers. I’m not saying they’re presented as sympathetic, but by the end of the movie, you begin to understand how they became the racist murderous assholes they are. It’s surprisingly easy, turns out. And if you don’t think that’s true, just keep your eye on that blunt metaphor pit bull, (their weapon of choice).

It also helps that the actors are universally excellent. Antonin Yelchin is the de facto hero, and sensibly so; he’s probably the least “punk” member of the band, and almost fills the usual heroine-in-distress role; it's Alia Shaukat, the band’s sole female member, who is pretty much the leader of the group. (And I'll gladly accept Shaukat as our new scream queen; this combined with her performance in the excellent The Final Girls proves she's up to the task). And Imogen Poots, (I'll just never get over that name), continues to impress in every role she has.

And then there’s Patrick Stewart, as the leader of the skinhead clan. The movie's getting a lot of publicity because of his presence, and there's no doubt he's good. But it almost feels like lazy casting. He's bald! And he's British! Done! And while he's certainly a chillingly calm bad guy, I never really bought him as a skinhead. Throughout it all, he just doesn't seem ignorant enough.

Though, perhaps that's the film's ultimate message: Don't assume stupidity or ignorance where outright evil may exist.