Now that Pauline is about to marry Malcolm (Jack Black), a self-loathing artiste of no particular metier, Margot is returning to the family's island beach house for the nuptials. And also to mine new material. And also to see if she can go 2 for 2 in destroying her sister's liaisons.
The in-your-faceness of their confrontations, manipulations and emotional triangulations - not since Who's Afraid of Virginia Woolf? have there been emotional head-butts like these - may well trigger a contact anxiety attack.
Baumbach, whose prior film The Squid and the Whale likewise explored the pathologies peculiar to the literary tribe of the American Northeast, is a cultural anthropologist who examines his subjects with a gimlet eye and unforgiving heart.
As in his previous movie, the boho habitat he studies is one where narcissism is the norm. Likewise unfulfilled ambition and domestic tumult. Divorce is frequent, with children the collateral damage. In this social order without order, the adults are childish and the children parent themselves.
Kidman makes Margot's narcissism both frightening and darkly funny, coddling, then castrating everyone in her orbit, from her adolescent son, Claude (Zane Pais), to her sister's intended.
Where Margot bigfoots the story, Pauline nips at her well-turned heels - the only way she knows how to slow down her marauding monster-sister. Mostly, though, as the drawling Pauline, Leigh (making her first appearance in a movie by her director husband) adopts a defensive crouch, armoring herself for Margot's next zinger.
Despite the careening car and Harris Savides' camera that pries indecently into the characters' faces and business, there's not much forward movement in Baumbach's film.
It is a succession of skirmishes in an ongoing war that succeeds as a showcase for two memorably fierce performances, Kidman's and Leigh's, and a sensitive turn by Pais as Margot's sexually indeterminate son. As actors, they are nervy and unnerving.
There is a second metaphor in the film, one not quite so effective as the dinged-up Volvo. It is a tree with rotten roots. It is the family tree. Will it fall? Or will someone chop it down?
Some call Margot a comedy. For me, it is a tragedy impaled by comic moments. It's the kind of experience Horace Walpole described when he observed, "The world is a comedy to those that think, and a tragedy to those that feel."
Contact movie critic Carrie Rickey at 215-854-5402 or email@example.com. Read her blog, "Flickgrrl," at http://go.philly.com/flickgrrl/