Two of the biggest craniums in cinema are at loggerheads in Cyrus. They belong to John (John C. Reilly), a ringer for Shrek, and the eponymous man-child played by Jonah Hill, whose submerged neck forms a halo—like the frame around a medieval portrait of a saint. But, like the painted saints of way-back-when, there’s something eerie, ivory, impassive in his features: his iceberg eyes and mouth agape. He bears a passing resemblance to his beloved ma, Molly (Marisa Tomei). She has the sort of long-lashed brown twinklers that could either be kind or too kind; they camouflage her thoughts. Despite being out of his league, she hits it off with John—who’s seven years on the rebound—after she catches him releasing into the bushes his intake from a hitherto luckless mixer. He’s shit-faced enough to stop fretting over his lackluster social skills; he cranks up the stereo when an old favorite pops on, and Molly is the first to sing along. Unfortunately, this scratches the needle on her 21-year duet with the almost-22-year-old Cyrus, who’s just a few retinal stabs away from being the Oedipus to her Jocasta.

But this movie’s aim is not to be a bom-chick-a-wow-wow Greek tragedy; and it wouldn’t be quite fair to compare it to other mother-lovin’ comedies, like Murmur of the Heart or Spanking the Monkey, in which genealogy is actually defied, and the kinfolk really do get kinky. Rather, it’s spawn of a more standard form—an inversion of Meet the Parents—though, in technique, it’s very different. The writing credit allotted to the directors—the brothers Mark and Jay Duplass—may be largely symbolic; according to Reilly, “90% of the movie is first or second takes.” It’s as if they were importing the concept of sustainability to film; but the honesty that’s composted doesn’t quite jibe with the comedic potentialities heaped on the trash pile. They seem indisposed to break past slaphappy gentility, so Cyrus coasts on its delicate charm, like a bodyboarder riding the mellow whims of a glassy morning tide. Clearly, the Duplasses—masters of mumblecore—didn’t want to grease up their style, and harsh their (critical) buzz. This is their first sort-of-marquee-name cast, and their first sort-of-big-studio (Fox Searchlight) production. Despite the salable simplicity of their plot, it was good of them not to crumble to commercial tastes.

The mainstream comic movies today have alarmingly effective defense mechanisms. The specter of big-daddy postmodernism is certainly to blame; something like The Hangover is insulated by our society’s dwindling gamut of sexual taboos (even the culture warriors have cozied up with this sort of safe sex, emasculating the satirists’ sting), the fungibility of the fungal jokes, and the pop-cultural echolalia, the references that feed off one another. Ergo—to my tastes, at least—the less affected the bonehead comedy, the more purely enjoyable. Ambitions can be crippling when the audience wants an easy laugh. Turning their laughter against them when they seek the safe-bet mindlessness that a certain class of comedy is a shoe-in for can come off as a betrayal. I don’t mean to sound condescending; smarty self-consciousness in this type of movie can slaughter laughter, and lead to a posture of condescension that may not have been intended. Witness Hot Tub Time Machine from this year, or Observe and Report from last; neither were hits. Despite my reservations about them, I did sense creative intelligences at work—if sometimes slacking off. They were trying to latch onto the frat-pack school of comedy, headquartered in decaying Guyland—or, if you’ll permit me, Brahpolis. Unfortunately, they also wanted us to know how distasteful Brahpolis is—and even if they’re right in finding the milieu rather slimy, there’s no better way to snag a laugh in ice-cold intellect, restricting its access to the mouth, than by sucking up to something while cussing it under your breath. (An Apatow production like Pineapple Express isn’t really an exception. The actors flirted with satire, but the filmmakers couldn’t sustain the winkiness, and welded both eyes shut. It became a shoot-’em-up, and bungled another genre.) So, as ironic-funny as Rob Corddry was in H.T.T.M.—he has a better outlet on the show Childrens Hospital, now on Adult Swim—his lines became grating. The filmmakers just didn’t get that Will Ferrell himself is a parody of fatuity. (The trouble is that he’s been impersonating George W. Bush for too long; playing him as a harmless, good-natured dolt just doesn’t quite cut it for me anymore.) By attempting to parody a style too self-conscious (and too self-consciously lowbrow) to lampoon, the filmmakers ended up degrading themselves.

You can’t satirize Brahpolis within its city limits, but you can within your own niche, or in the freeing light of realism. Though Lynn Shelton’s Humpday did not critique Guyland, or at least not its typical habitués—the shameless self-caricatures who populate Jersey Shore—it did touch on the bromantic gray areas that remain taboo to bozos and bohemians alike. It was like Bob & Carol & Ted & Alice for a time of post-sexual-revolutionary capitulation, or a weak-tea Americanization of Alphonso Cuarón’s brilliant, electrostatic Y Tu Mamá También. Weak tea, but sweet tea. Shelton directed the 2009 problem comedy—about a pair of straight college buds who decide to star in a gay porno together—in mumblecore fashion, and there were briar patches of revelation and fascination in the off-the-cuff interplay; but it too was marred by hyperconsciousness. With an introspective filmmaker like Mark Duplass cast as one of the leads, the film awkwardly went about doing the audience’s interpretive work for us, and I felt that bogged the picture down. But how can it be avoided anymore? That sort of hippie-lineage let’s-talk-it-out bullshit is imprinted on this chastened generation. I hate to castigate honesty.

Cyrus, peopled with some top-notch troupers, doesn’t suffer from self-conscious neurosis; but it’s also a little touchy-feely. In sum, it’s rather provincial: a sunny black comedy; sunrise-gray with the attendant warmth and dew; strangely, Tantrically centered and peaceful. Lovely. I’m not trying to be a smart-ass; like the Duplasses’ 2008 Baghead, Cyrus makes virtues of simplicity, pleasantry, and a dignified concern for its characters. But the distended dénouement, which has been unfairly dismissed as “commercial,” instead points to the filmmakers’ almost obsessive idealism, a naïveté carried over from the improbably tranquil resolution of Baghead. The happy ending isn’t a concession, but it’s an aesthetically dubious choice—far too quick and painless. For a few stretches, I hadn’t laughed so hard since Bad Lieutenant, back in March; but I didn’t chuckle as long as I’d hoped.

Hill is a surprisingly versatile comic actor. He’s 180 degrees away from the sex-crazed boor that made his name in Superbad. He’s still playing a virgin—I gather—but this celibacy seems self-imposed. Despite being an ascetic of sorts, Cyrus is no Jesus freak; he’s shaped like Cupid, but has poison darts in his quiver. So long as the arrows are being shot, Hill is in top form—shifting from guilelessness to inscrutable calculation. The performance hits a wall, however, as soon as John and Cyrus reconcile. Reilly’s pain is too real when John breaks down; he’s violating the rules of improv, shifting genres, and Hill isn’t sure how to respond. Then again, how could Hill be expected to pull off such an undefined turnaround in his character? It’s like Cartman, on South Park, becoming a diplomat. But there are so many conflicting elements at play when Cyrus shows off his electropop compositions for Joe-Schmo John that my laughter must have disturbed the patrons in the rows behind me. Here’s this dead-eyed, tubby creep, who shares bathroom time with mommy, playing jams for clubs that wouldn’t even let him in.

Hill has a fine rapport with Tomei, but her shtick here is to play clueless and ditsy. (One probably can’t blame her entirely. In terms of the scenario, Molly’s more pivot than person.) It’s fine, but it seems to put in a vise the tough cookie who roughed out The Wrestler, and the brassy, hoop-earringed dame who squawked triumphantly through My Cousin Vinny. All this improvisation may be counter to her style and training, though she aces her romantic scenes with Reilly, even as she slinks around all soft and mousy—against type. They share the same curly clown wig, which, as Dr. Steve Brule, Reilly used much to his advantage. Reilly can go from Boogie Nights to Chicago to Step Brothers with ease; but, save for the prenominate snafu, this is probably his richest performance. What separates Steve Brule from Ferrell’s NASCAR lackey in Talladega Nights is a core of sadness, vulnerability; and he imports that melancholy, so clearly close to the thespian’s heart, to Cyrus—and without the usual dumdum overlay. John, the freelance film editor, is emotionally vulnerable, not mentally. This should fling open the door to real comedic terror; Cyrus should be that manipulative, mind-fucking monster who has no qualms about the innocence of his victims, with John as his helpless patsy. But the Duplasses only keep the door ajar.

Still, these filmmakers are almost irresistibly likable. They have even wooed another pair of siblings—Tony and Ridley Scott—into an unlikely alliance with them; the Scotts are credited as executive producers. But, good and good-natured as Cyrus and Baghead are, I’m not sure whether the Duplasses are capable of a truly major comic work. They are proficient within a small scale, and that’s a gift. But they scale back, too, on the payoffs; the culmination of John and Cyrus’s rivalry is a fracas at John’s ex-wife’s wedding. Hill acts demoniacally, but Cyrus would be kicked out of hell for good behavior. Our fears for John are assuaged too early; Michael Andrews’s anodyne anti-folk score is like elevator music that consoles us just as we want to get freaked out. The Duplasses’ sweetness and modesty are virtues, but it blanches their comedy. They may never really be in the black.