When Melanie Lynskey’s Ruth, a depressed nursing assistant, goes to the home of the thief who stole her laptop and grandmother’s silverware, the thief’s father offers to pay her off. When she refuses money he asks, “Well what do you want?” “Everyone to not be such an asshole,” she says earnestly. In I Don’t Feel at Home in This World Anymore Ruth is on a mission, not just to get her belongings back, but to try to understand why everyone around her perpetually sucks.

The film, the directorial debut of actor Macon Blair, finds Ruth consistently stewing in frustration and pissed off at the general crappiness of everything and everyone around her. Despite the “no dog poop” sign on her front lawn, a dog keeps crapping there, and she reluctantly scoops it up each time. After a stranger at a bar blatantly spoils the book she’s reading, she just sits there, silently seething in annoyance. She picks up a bag of chips a man at the grocery store heedlessly knocks off the shelf. In the smallest of ways, Ruth takes on the burden cleaning up the ugliness and indecencies of those around her. But it’s not until her home is broken into that she finds an outlet for all that bottled up anxiety, and soon a timorous, passive woman transforms into a badass, ruthless heroine.

I Don’t Feel At Home, part quirky comedy, part gruesome thrill ride, finds the always-charming, always underrated Lynskey in full-on ass-kicking mode, carrying the film from start to finish. When the police fail to investigate the break-in, she recruits her weirdo neighbor, a rat-tailed weapons enthusiast named Tony (Elijah Wood), to track down the thief. The two find comfort in their mutual awkwardness, and the first half of the film plays like a standard Sundance dramedy, but eventually things take on a more absurd tone as a film morphs into a violent thriller. Relatively calm situations turn dangerous in a matter of seconds – a finger suddenly get snapped backwards, body parts are blown off by a shotgun, and a handful of nasty punches will jerk you out of your seat.

You may not know Blair’s name, but his face will be familiar to fans of Jeremy Saulnier’s work. Blair played Dwight, the revenge-thirsty vagabond in 2013’s Blue Ruin, and the neo-Nazi bouncer in Saulnier’s Green Room. There’s no doubt he’s learned a thing or two from Saulnier’s style, whose fingerprints are all over I Don’t Feel at Home, from the quick bursts of grisly violence to the taut editing and menacing score, composed by Blair’s brothers Will and Brooke, who also worked on Saulnier’s films.

The three films also share a theme about reserved underdogs who become the valiant heroes of their own bleak narratives when pushed too far – Lynskey’s Ruth is reminiscent of Blair’s Dwight, only with less serious motives for vengeance. That difference between the two characters, and the less serious subject matter of I Don’t Feel at Home, is what sets Blair’s film apart and highlights what’s missing. Where Saulnier’s work is fraught with tension and finds characters entwined in drastic, life-or-death circumstances, the stakes aren’t nearly as high in Blair’s debut. That wouldn’t necessarily be a bad thing if Blair didn’t gloss over the surface of Ruth’s existential woes and depressive melancholy. The film broaches serious topics, even injecting a half-baked religious background for Tony, but never quite develops them. There’s a missed opportunity to explore the depression, isolation, and loneliness that ails both Ruth and Tony, which could’ve lent the film a richer emotional arc and made their relationship more compelling and memorable.

Although it’s sometimes uneven with somewhat underdeveloped characters, I Don’t Feel at Home is nonetheless a clever blend of two very different genres. Blair’s mix of humor and feverish violence works best in the film’s final act, when things turn completely nutty. One fantastic shootout finds blood (and other bodily fluids) spewing across a lavish living room. It’s as hilarious as it is shocking, and it’s moments like that, straddled between queasy shock and laughter, when I Don’t Feel at Home in This World Anymore is at its best.