When Noah Baumbach decides to share his life with an audience, he means it. The writer-director’s painful new film “The Squid and the Whale,” which addresses his parents’ mid-80s divorce, comes from a deep, lonely place that most movies are afraid to mine. While the film crackles with wickedly funny observations and dialogue, beneath the humor is a tragedy so heavy that some of the jokes elicit more tears than laughs. Forgoing much of a plot, “The Squid and the Whale” is fundamentally about two well-honed concepts: what it means to have a family and what it is like to watch that family disintegrate. Baumbach treats both without flinching, creating a rare movie that tells its story both honestly and artfully.

The reality of divorce is starkly exposed in a wispy plot that functions as a series of vignettes. “The Squid and the Whale” begins with a sharply written tennis match between the soon-to-be ruptured sides of the Berkman family. The anger and discomfort of the game, which no one seems to like but everyone wants to win, characterizes the eroded state of Bernard (Jeff Daniels) and Joan Berkman’s (Laura Linney) marriage. When the two officially divorce shortly thereafter, their two boys pick sides: Frank (Owen Kline) siding with his mom and Walt (Jessie Eisenberg) with his dad.

Adolescent Walt clings to his father, a washed up writer now paralyzed by his bloated self-image. But Bernard has no time for his son, instead carrying on an affair with one of his college students (Anna Paquin). Frantically trying to get his attention, Walt mimics his father’s pretentious sayings and mannerisms at school. He even dumps his girlfriend when his dad says that she is not pretty enough.

Frank, who is much younger, is obsessed with his mom’s paramour — tennis instructor Ivan (William Baldwin). Joan, busy with her own blossoming literary career, is oblivious to her son’s antics: filching alcohol from the fridge and — more disturbingly — masturbating in the school library and spreading semen on the books.

Both intellectuals, Joan and Bernard are too engrossed in self-analysis to think about their kids and the kids are too busy worrying about their parents to manage their own lives. All four seem lost in disparate internal realms.

Every performance in the film is pitch-perfect. Jeff Daniels camouflages himself behind the bushy beard of Bernard, a more human version of Gene Hackman’s Royal in “The Royal Tenenbaums.” Forced to live in poverty because he cannot sell a book – and too proud to work – he bitterly points fingers at everyone else, never taking responsibility for his own failings. Jessie Eisenberg also does a brilliant turn as Walt, boldly pursuing the wrong course to comically awkward result.

Bolstering his cast, Baumbach’s dialogue has the immediacy of thought patterns put into words, managing to be at once reminiscent of “Waking Life” and yet also to contain the quirky diction of a Wes Anderson picture. But, even better, his writing ultimately transcends these influences by cutting to the core of its characters’ emotions.

“The Squid and the Whale” is the opposite of ostentatious. Filmed on sixteen millimeter, Baumbach deftly wields a hand-held camera as if catching found moments in the act. Several of the subway scenes were even surreptitiously shot without a permit. Odd angles abound, showcasing the portability of the format and catching the characters from every side.

Oftentimes the film seems assembled like a school project by a precocious child — a young auteur who does not follow the rules. There is no beginning or middle in the “Whale,” and do not expect any sort of character arc. And right at its most intriguing scene, when it seems like something illuminating is going to happen, the film ends.

This story is not about growth, nor is it about Walt, Bernard or anybody learning a lesson. The children do not turn out all right in the end and neither do the parents. “The Squid and the Whale” is about what divorce really means for a family and what is ultimately at stake. Will the Berkmans be able to regain their autonomy or is the damage irreparable? In this shocking tour de force, Baumbach leaves it up to the audience to decide.