Step Brothers

Will Ferrell, his longtime director and writing partner Adam McKay, and their new pal John C. Reilly have made a movie that is basically for their own amusement. It is called “Step Brothers,” and while they have graciously permitted it to be screened in public movie theaters, don’t be misled. The people who will enjoy it the most are named Will, Adam, and John C.

The story is credited to all three of them, with Ferrell and McKay officially writing the screenplay and McKay directing. Comedy guru Judd Apatow was involved as a producer, lest an R-rated Hollywood comedy accidentally slip out the door without his name on it. I suspect he mostly stayed out of the way and let the boys do their thing.

As it happens, I often find “their thing” to be very funny, and I laughed quite a bit during “Step Brothers.” But is it a good movie? Not really, no. The two protagonists — 40-year-old Dale (Reilly) and 39-year-old Brennan (Ferrell), both live-at-home losers who become stepbrothers when Dale’s dad marries Brennan’s mom — are one-note sketch characters who seem less and less plausible the more time we spend with them. The story is nonsense. The whole thing is sloppy and slapdash.

And yet … there’s that laughter thing. Not only are Reilly and Ferrell well suited as a comedy duo (they first joined forces for “Talladega Nights,” also directed by McKay), but Richard Jenkins and Mary Steenburgen play their newly married parents with considerable gusto. The two reliable screen veterans, emboldened by the “let’s-shoot-for-an-R-rating” ethos of the production, ad lib all manner of potty-mouthed amazement over the immaturity of their children, and it’s often very funny. Steenburgen, as Ferrell’s doting, enabling mother, just seems happy to be here (she must love Ferrell, having already played essentially the same role opposite him in “Elf”), while Jenkins, his character quickly growing tired of his son and stepson’s uselessness, is a marvelous grump.

Dale and Brennan are essentially interchangeable. They’re unemployed, lazy, entitled, and emotionally stunted. They watch TV and look at dirty magazines and do very little else. If you met them in real life, you would assume they were mentally retarded. They are enemies at first, primarily because the film needs them to be, and they threaten one another with murder their first night of sharing a bedroom when Brennan and his mother move in.

But soon enough they’re best friends, forced by Dale’s dad to go out and look for jobs while harboring fantasies about launching their own company. Prestige Worldwide, it would be called. What would Prestige Worldwide do? Um, something about music, kind of. Dale plays the drums and Brennan sings, although he rarely does so if there are people listening. It seems he was traumatized as a teenager when his older brother, Derek (Adam Scott), mocked him publicly. (Derek, by the way, is a hilarious parody of tooly entrepreneurial SUV-driving bluetooth-earpiece-wearing douchebags.) But Dale insists Brennan has a beautiful voice. “It’s like a combination of Fergie and Jesus,” he says.

The films reminds me a little of last year’s “The Brothers Solomon,” which also had two developmentally arrested siblings, one of them played by an “SNL” alum, who lived in a world all their own. The difference is that “Brothers Solomon” had a certain discipline to its absurdity. It was logical in its own way. “Step Brothers” is more of the loosy-goosy, try-everything school, and while part of me admires that freewheeling spirit, the less charitable part of me calls it self-indulgent to film yourself horsin’ around for 90 minutes and then expect people to pay money to see it.

Even as an ardent lover of Will Ferrell’s comedic stylings, I’m forced to admit that this is far from his best output. It’s worth noting, however, that even a subpar offering from Ferrell produces more laughs than a lot of people’s best work. This one’s strictly for Ferrell, McKay, and Reilly — and for those of us who really, really like them.

B- (1 hr., 38 min.; R, abundant harsh profanity, a lot of vulgarity, brief strong sexuality, some nudity.)