At some point during the second half of Young Adult, after the protagonist has shown that she is not just a deluded narcissist but seriously mentally ill, the laughs become increasingly uncomfortable -- but they still come. This is a movie you can expect to make you squirm, though it is perplexing how Young Adult can be so painful to watch when you feel so little for its characters.

Mavis Gary is a 37-year-old failing ghostwriter with a failed marriage behind her and -- unless she makes a big change -- a serious drinking problem in her future. She is quick with an outrageous lie when it suits her purpose, but she visibly (and hilariously) struggles to deliver the blandest of basic pleasantries -- like congratulating a proud parent on their newborn baby.

The title is a dual reference to Mavis's job as an unbilled author of YA fiction and her rejection of grown-up conventions like childbearing, meeting deadlines, eating her vegetables and keeping house. Adult life has so disappointed Mavis that she operates as though she's half her age -- a task made easier for her remarkably youthful appearance and days spent immersed in the minds of fictional teenagers.

Though Mavis can still turn the boys' heads like she always could, she's fixated on the one that got away: We don't learn much about Mavis and Buddy Slade's (Patrick Wilson) high school romance or why Mavis was copied on an email announcing the birth of his daughter -- all we know is that she wants him back. Mavis, in her twisted way, interprets her inclusion on the announcement as an invitation to break up Buddy's marriage to an implausibly patient and good-natured special needs teacher (played, unsurprisingly, by Elizabeth Reaser.)

Though Beth is plenty attractive and perfectly secure in her marriage, there's no way a real-life human would encourage her husband to spend more time with his knockout high school sweetheart who makes no attempt to conceal her intentions. Still, Beth's improbable warmth towards Mavis gives the latter an opportunity to deliver one of her more sensible lines during a climactic meltdown.

Along the way, Mavis's chance encounter with a disabled former classmate (who she does not recognize though his locker was next to hers for four years) develops into the closest thing Mavis can have to a real friendship. Matt (Patton Oswalt) was the victim of a misguided hate crime in high school which left him unable to walk without the help of a crutch, and forced to urinate, etc. in the wrong direction. His attackers presumed he was gay, and though the assault initially made headline news, Matt tells Mavis that he was forgotten soon after it came out that he was straight. Still, everyone in town knows who the hate crime guy is.

We get the sense that Matt has spent many a night drinking alone at a bar where everybody knows his name -- he lives with his unfortunate sister, who barely tolerates him, and shows no sign of ever having had a real friend or a girlfriend. The friendship may be unlikely, but it's not difficult to understand: Matt is enamored enough of Mavis's beauty and legendary status that he allows her to monopolize his time and attention, but he's too angry and cynical to act as a fawning enabler. Of course, Mavis is happy to be in the company of someone who knew her when she believes she was at her best.

You're a piece of work, Matt tells her over the wreckage of way too many shots of Maker's Mark. You're a piece of sh-t, she replies, before they exchange a brief but affectionate smile. But even after that affection has led to a kind of intimacy, Matt won't let Mavis off the hook: Reminding her that she looked at the heart-shaped mirror inside her locker far more often than she ever glanced at him -- when he really was at his best.

Since Mavis Gary is very likely a sociopath, it's impossible to believe that she will ever conquer her (very scary) demons. But it's also impossible not to be amused by her brazen disregard for reality or anyone else's feelings but her own. Her deluded self-absorption is so extreme that she likens her former flame's happy family to a disease -- telling him we can beat this thing together.

Director Jason Reitman and writer Diablo Cody (who previously teamed up for Juno) were too careful not to let Young Adult slip into paint-by-numbers homecoming movie territory -- wringing out the warmth along with the indie comedy clichés. Still, they've delivered a patently entertaining movie that will keep you laughing even though it won't make you happy.

Expect major award nominations for Theron and Oswalt, and -- if there is justice -- a nod for the art direction, which at times tell the story better than the script.