Lorene Scafaria's Seeking a Friend for the End of the World is being promoted as a human comedy about the apocalypse, which is probably a wise move, and there is plenty of that flavor in it. However, that makes it sound like a one-joke premise, a goof, some kind of light comic riff on Melancholia or 4:44 Last Day on Earth. But this is a movie that takes its premise as seriously as those dour pictures did, and works outward from there. It's a funny movie, yet it keeps the darkness right under the surface, for easy access.

In the opening scene, Dodge (Steve Carell) and his wife (played by Carell's real wife, Nancy) are sitting in their car, getting word that an Armageddon¬-style attempt to destroy an asteroid headed to earth has failed. They've got three weeks before the end of the world, according to the radio disc jockey, so they'll be doing a "countdown to the end of days, along with aaaaaall your classic rock favorites!" And then "Wouldn't It Be Nice" plays, and Dodge's wife flees.

Back at their apartment, he meets a neighbor, Penny (Keira Knightly), who is going through a bad breakup with her boyfriend. She asks about Dodge's roommate, and "that guy she was always with," the one who seemed to make her so happy. And she hands over some of his mail, which includes a letter from the girl that got away, oh those many years ago. Eminent death will make you follow up on things like that. As rioting and looters approach their building, he and Penny make a getaway, and hit the road.

Carell and Knightley are rather an unlikely pairing, but they've got a strange chemistry that works--their back-and-forth is exquisite (Her: "I did ruin your life." Him: "I had a really good head start") and their characterizations are both rooted in their familiar personas, and beyond them. Carell is particularly good, adopting a deep, Bill Murray-esque melancholy and shrugging sense of accepting the inevitable. Knightley's character flirts with Manic Pixie Dream Girl preciousness, but imbues the character with a humanity that transcends the type; she's got a lovely monologue at a key moment in their arc (concerning her love of vinyl, of course) that moves the film into the realm of pathos with an almost invisible dexterity.

That move is made easier by the bleak undertones that pulse in even the film's funniest scenes; Scafaria's marvelous script chooses not to ignore the darkness at its center, but to embrace it, and then go for gallows humor. An early sequence, of a dinner party gone awry, is a little comic masterpiece; the great Melanie Lynskey shows up in jewels, a party dress, and a tiara ("It's everything I never wore!"), Patton Oswalt drunkenly endorses consequence-free casual sex, and Connie Britton cheerily announces, "Sarah and Dave brought heroin!" ("You don't have to do heroin if you don't want to, sweetie," she assures Carrel later.) This is a funny scene, but they're not pulling punches: it's got drinking kids and incest jokes in it. Drink up!

Scafaria stages a similarly hedonistic sequence further on down the road, at a Chili's-style chain restaurant called "Friendly's," where the wait staff is out of their minds on ecstasy and a full-on orgy seems a "Mudslide" away. (Gillian Jacobs and T.J. Miller couldn't be funnier here.) But Scafaria doesn't just excel in the big set pieces; the film thrives in its small moments, in the tiny interactions between its leads. This is her directorial debut, after writing the charming if forgettable Nick and Norah's Infinite Playlist, and she's got a good eye; it's a dialogue-driven film, but she finds some oddly haunting and beautiful images. The film occasionally broaches heavy-handedness, corniness even, but that's forgivable; Safaria shows an impressive command of tone, particularly in the final scene, where she's doing two seemingly incompatible things, at the same time, and beautifully. Seeking a Friend at the End of the World is a peculiar, unique, and richly rewarding film.

Jason lives in New York. He holds an MA in Cultural Reporting and Criticism from NYU.