Building on the critical success of his 2013 blood-soaked revenge thriller Blue Ruin, indie genre darling Jeremy Saulnier returns with another slick piece of nastiness: the relentless and nerve-shredding Green Room, which ostensibly seeks to redefine the nightmarish scenario of "wrong place, wrong time." On the last leg of their financially disappointing tour of the Pacific Northwest, D.C.-bred punk band the Ain't Rights accept a gig at a rural club to help fund their trek back across the country. The band members -- Pat (Anton Yelchin), Tiger (Callum Turner), Sam (Alia Shawkat), and Reece (Joe Cole) -- are uneasy when they discover that the backwoods venue is a neo-Nazi stronghold, but they're just hoping to load in, play, and get the hell out of dodge. When the Ain't Rights take the stage, they lurch into a cover of the Dead Kennedys' "Nazi Punks F. Off,"" antagonizing the already pissed-off boots-and-braces crowd. A few beers are hurled in their direction, but the rest of the set goes off without incident. Despite the attempts of a burly bouncer (Eric Edelstein) to keep the band away from the backstage room, they retreat to the titular space only to find a young woman with a pocket knife in her temple and a swath of skinheads standing around her. They've clearly seen something they shouldn't have, and the skins are forced to go into damage control before Pat can call the cops. Along with the murdered woman's best friend Amber (a Chelsea-cut Imogen Poots), the Ain't Rights are held hostage inside the dressing room as the venue owners decide how to defuse the situation, calling on their deliciously devilish leader Darcy (Patrick Stewart, who seems like he's having the time of his life in this role) to run point. The neo-Nazis turn out to be a well-oiled gang rather than a bunch of confused rural racists, and the band's situation becomes increasingly dire. From here, Green Room escalates into a cacophony of tension and spilled viscera as the group try to escape from the skins, their struggle recalling the tagline on the original poster for The Texas Chainsaw Massacre: "Who will survive and what will be left of them?" The violence arrives quickly and ceaselessly as the punks hatch a series of escape plots, and the film ratchets up the pressure along with the body count. As is the case with any escape movie, there are only a few ways this whole thing can go (as Darcy candidly reminds his hostages); regardless, Saulnier's steady hand and Sean Porter's claustrophobic cinematography give this thriller sharp pacing, grisly imagery, and adrenaline-pumping set pieces. Saulnier fills Green Room with plenty of small but perfect details: Whether it's the carefully curated bumper stickers on the band's van, living-room zine interviews, or the Minor Threat tee sported by Yelchin, Green Room is dripping with punk authenticity that will immediately resonate with anyone who's sweated through a basement show or slugged cheap cans at a dive-bar gig. The director does right by the subculture, and harnesses its spirit in both the attitude of his filmmaking and a shrewdly curated soundtrack. As is the case with Saulnier's previous two features -- the aforementioned Blue Ruin and 2007's Murder Party -- Green Room is full of gruesome visuals that some viewers won't have the appetite for. It's a mean little piece of horror, but it's still an expertly acted thrill ride: Poots, Yelchin, Stewart, and Macon Blair (playing a conflicted gang henchman) deliver great performances amid the bleakness, with the bucolic Oregon setting and meticulously decorated venue providing a convincing backdrop for the actors' desperation. Saulnier has his finger on the pulse of the audience throughout the entire flick, and his understanding of genre filmmaking is a force to be reckoned with.