“Elling” (MacAdam Cage, 300 pages, $23), a comic novel by the Norwegian writer Ingvar Ambjørnsen, has already enjoyed life as a novel in the author’s native country, as a play, and as an Academy Award-nominated film, and it’s easy to see where its off-kilter appeal lies. Imagine Oscar and Felix — or, as its culturally aspirant title character might prefer, Vladimir and Estragon — as recent inmates of a mental facility called Brøynes Rehabilitation Centre, who now share an apartment in Oslo. Elling is hot-tempered, pan-phobic, and prudish, and considers himself something of a budding poetic genius; Kjell Bjarne, his roommate, friend, and foil, is a burly, slow-witted hulk of a man with spotty personal hygiene and a costly addiction to phone sex. Both are hesitant about leaving their apartment and must slowly reacquaint themselves with the hurdles of everyday life; early on, with the help of their caseworker, they manage to take in a movie and visit a pizzeria, a feat that nearly maxes out their collective social capability. In the course of the novel, the challenges become significantly more daunting.

The thrust of the story comes when the two men return from a (barely achieved) evening out to find a pregnant woman passed out on the stairs of their building. Elling initially reacts with his uncompromising — and wonderfully ludicrous — sense of moral indignation. “We disapproved of drunkenness in any form,” he explains on behalf of the both of them, “but drunken women were absolutely scraping the barrel.” Nevertheless, they work up the courage to carry her back to her apartment, one flight above theirs, where Kjell Bjarne stays and looks after her. The woman, who turns out not to be terribly bright herself, is named Reidun Nordsletten, and beyond immediate logic she starts up a winsome romance with Kjell Bjarne, about which Elling feels alternately threatened and supportive. (Neither man has known the touch of a female hand, so the possibility of any erotic experience completely baffles them.) With Reidun’s arrival, a classic scenario takes shape — the male bond disrupted by a woman — with anything but conventional participants.

As Kjell Bjarne (he is referred to throughout by his full name) navigates the ways of love, Elling pursues his newfound literary ambitions. Specifically, having written a single poem, he goes about etching it into stalls in restaurant bathrooms and hiding copies between products on supermarket shelves. His ultimate goal is to insert the poem into sealed boxes of sauerkraut (soup packets prove impenetrable), which he imagines will earn him anonymous recognition by the city tabloids. (“Sauerkraut Poet Strikes Again!” is one headline he dreams up.) At a poetry reading, where he sits by the bar in sunglasses hoping to give off the impression of “a free and easy spirit, someone who scribbles down a prose poem on the restaurant bill to give the waitress food for thought, before stumbling out of the restaurant and taking another draught from the goblet of life,” he befriends a kind old gentleman named Alphonse Jørgensen, who, it turns out, is also a poet, in the more traditional sense of having written and published poems. Alphonse is the final member of this crazy clique, and the four of them — two obsessive-compulsive buffoons, a pregnant lady, and a man of letters — embark on a series of high-strung misadventures that carries hints of screwball comedy, road novel, and coming-of-age tale for the borderline sociopathic.

At heart, though — and there’s much heart to be found in it — Mr. Ambjørnsen’s story is an ode to friendship and an exaggerated study of the difficulties of getting on in the world. The novel has a engagingly oddball sense of humor and a finely detailed depiction of its peculiar protagonist, whose greatest hope for his new life is to be a “balanced, discontented underground poet with a small circle of friends.”

Mr. Ambjørnsen’s greatest asset may be his light touch; none of the characters are tagged with the kind of self-conscious quirks that tend to show up in portraits of lovable nitwits. (Succesful American indie films like “Sideways” and “Little Miss Sunshine” have struck a similar balance.) In fact, Elling’s heightened neuroticism and calculated pose of sophistication may be so convincing as to elicit twitches of self-recognition: Who among us has not sat on a barstool trying to look mysterious? Mr. Ambjørnsen is fully invested in his characters’ warped reality, but tempered enough not to imbue the lives of the mentally imbalanced with inflated meaning.

Elling, on the other hand, doesn’t hold back when given the chance to wax profound. Between social pratfalls, he offers stray bits of wisdom, as when he explains to Kjell Bjarne “how wonderful it was that we humans were so different.” Kjell Bjarne nods and offers “that no two snowflakes were identical. It was something I would have never have expected of him, to be quite honest. He had grasped my meaning, even though what he said was beside the point, of course. Naturally, I had been thinking most about living organisms, and I clarified this.”

Mr. Schulman is on the editorial staff of the New Yorker. He last wrote for these pages on Alan Bennett.