Adults in Noah Baumbach's movies especially his celebrated last film, The Squid and the Whale, and his new family drama about the fractured relationship between two sisters often behave poorly. They can be petty and casually cruel and scrape at their loved one's jugulars from across the dinner table. They're funny, too. You may see a lot of these messy people at home for Thanksgiving but rarely on film at the multiplex. After Nicole Kidman, who plays the neurotic, graspy Margot, and Jennifer Jason Leigh, her sister who's getting married, shot their first big scene together, they were both plagued with stomach pains from the sharp tension between their characters. The script captures ''the worst of all your family dynamics coming into play,'' says Leigh, ''and everyone's trying so hard to rise above past hurts.''
Jack Black, playing the fiancé, whom Margot frowns upon, might not seem an obvious fit for this complicated world. But he sought out Baumbach after seeing Squid, and the director took to him immediately. Leigh, usually cast as the fidgety, disturbed type, gets to tackle a breezy, warm woman for once. And Kidman, after a run of remakes, returns to what she describes as ''the tone of humor in To Die For.'' Leigh says the whole cast got on like family just the strange kind that actually gets along.