This is a festival that places a premium on youth. It’s nobody’s fault. The world places a premium on youth. But halfway through Andrew Bujalkski’s great new comedy, Results, it occurred to me that I was watching a movie about adults. Sure, the characters are just as lost as some adolescents — but the film is about the particular loneliness that comes from knowing who you are, but not what you want.

Results is set in and around an Austin gym owned by a personal trainer and aspiring fitness guru named Trevor (Guy Pearce). When a miserably divorced, newly wealthy, recently transplanted New Yorker named Dan (Kevin Corrigan) drops in looking for house-call sessions, Trevor reluctantly pairs him with his most aggressive trainer, Kat (Cobie Smulders). But Dan is more interested in companionship than getting in shape. When Kat demonstrates how she’d like him to perform a squat, all he does is look at her ass.

When he invites her to get high with him, she surprises herself — and us — by sitting at his kitchen counter and inhaling from his pipe. He thinks this is romance. She doesn’t know what she’s thinking. Things go comically south. Trevor steps in to chastise Dan in Kat’s honor, but eventually finds himself becoming a friend. And as you’re watching, you’re never entirely sure where Bujalski is taking this thing. That’s partly the source of its exhilaration: He’s written this movie beautifully, but it doesn’t follow any conventional script.

Results is Bujalski’s fifth feature. The amateur acting and low-fi emotionalism of his 2002 debut and 2005 follow-up — Funny Ha Ha and Mutual Appreciation — marked the arrival of a special filmmaker. But other directors (most notably Joe Swanberg and the brothers Jay and Mark Duplass) were doing similar work in which inarticulateness, narrative inertia, and a dearth of formal technique coalesced into a style: so-called mumblecore. That style wasn’t exactly new. It’s a generational rite of entitled youth: Before we live, we’ll slack! But a little of this iteration went a long way; the movies ranged from anti-experiential to simply execrable.

Bujalski is 37 now and easily the most talented filmmaker to come out of that moment. (His previous film, a tournament comedy called Computer Chess, is pure formal magic.) With age comes experience. And like the Duplasses and Swanberg, Bujalski is allowing that experience to inform his filmmaking. Results is his first film entirely with professional actors, which must be like getting state-of-the-art equipment after years of making do with less.

Bujalski actually did wonders with amateurs. As personally opaque as the characters were, the worlds he built around them had the illusion of transparency. Pearce, Corrigan, Smulders, and the rest of the cast allow Bujalski to reach another level. None of the lead parts is easy. Smulders perfectly calibrates aloofness, confidence, and fury without blowing a gasket. She’s not going for depth, but makes the role unpredictably funny and mysterious anyway.

Corrigan, meanwhile, is a shock. He’s in the pantheon of independent-film character actors (it wouldn’t be Sundance without him), but has never been stronger. With his thinning hair, Bronx accent, and creepy air, he typically plays losers. This is one of the very few that culminates in a win. This is also the loosest (and most flamboyantly fit) Pearce has ever been. He gives the part amazing interiority and something close to his own Australian accent.

Even with characters as depressed, lovelorn, and weird as these, the actors give the lines and reaction shots brightness, sharpness, and contrast. (As a soused, slacking, indecipherable real estate lawyer, Giovanni Ribisi mockingly personifies mumblecore.) They bring to life Bujalski’s sideways sense of humor. Results plays like a commercial comedy — it’s set to be released by Magnolia, which, with this and Tangerine, has two of the very best films here — but one operating exclusively on the terms of its maker. It’s built entirely around behavior and decisions. If Dan can’t have Kat, he thinks Trevor should be brave enough to admit that he wants her. It sounds juvenile, but you partially understand his hesitation. He’s used to being on his own (his dog is his bed-mate), and commitment is scary — especially with someone who kind of scares you, as Kat does him.

This is probably the first American movie since James L. Brooks’s Broadcast News to attempt to psychologically dramatize the misalliances and emotional microclimates among three strong, human-size personalities. Like Brooks, Bujalski thinks our work partially define us (the kids in his first two movies were jobless, accounting for the lack of definition). But Bujalski’s pragmatism tends more toward optimism. It’s funny: Before Results started, two friends were talking about the good cry they’d had at a different film, which made me envious. But when Results was over, my eyes were wet too. They were tears of severe happiness.

♦♦♦

Sundance Film Festival

For almost a week, people have been talking about the Puritan horror film The Witch, which is in the dramatic competition. It’s ingenious; no, it’s not; yes, it is. I’ll just say that I watched it yesterday sandwiched between two people who at various points grabbed for me in fear. I’ll also say that when a character is attacked by something outside the camera frame, I jumped and screamed for Jesus. With a horror movie, competence can get you far, and The Witch is one of the most competently made of this era, in which things like production design, framing, editing, and painterly beauty are impossible to come by.

The film is set in 1630 New England and opens as a religious settler family of seven begins life on its own after being cast out of its community homestead. One day, the eldest child is playing peekaboo with the youngest. When she removes her hands from her eyes, the baby boy is gone. A caped figure sprints with him through the woods, then it does something terrible. The baby’s vanishing sends the mother into hysterics and unleashes a series of strange events.

According to a postscript, the bizarre events and lyrical dialogue (“This is unnatural providence!”) have come from period documents, which the writer and director, Robert Eggers, making his debut, fashions into a gross Gothic that sees the eldest daughter (Anya Taylor-Joy) accused by her younger twin siblings of being a witch. She denies it, but she just milked blood from a cow, so honestly, who can say?

Eggers is a production designer, and he can direct. I can remember almost every image in this movie, even the ones watched squeamishly with only one half-open eye. He can handle wild farm animals and bad-ass children with delicacy and precision. Young Harvey Scrimshaw, the actor who plays the eldest son, Caleb, nails a devastating sick-bed aria that makes Daniel Day-Lewis look like Pauly Shore. Eggers (and the composer and sound designers) establishes an air of dread that never wanes. But here’s the thing: None of it amounts to anything. Eggers forgoes any ambiguity. This is really happening.

But with horror — good horror, anyway — that provenance, natural or otherwise, is important. The terror ought to build (and it does here), but so should the meaning. And despite all this craftsmanship, the randomness starts to get on your nerves. Hitchcock and his great counterfeiter, Brian De Palma, rarely relied on logic, per se, but they could conjure a sense of insanity or concentrated terror so that you had a sense of what or whom to fear. Even a Final Destination gives you that. Eggers is hobbled by these documentary accounts. He can’t make sense of them either. Nonetheless, I’m impressed that the festival programmers didn’t shunt The Witch to the catch-all Next section. It deserves consideration from a jury that includes Edgar Wright. Even if Eggers can’t give you a single good answer, he gives you a very good time at the movies.