Bob Vergara/Sony Pictures Classics

From left are Mather Zickel as Kieran, Anne Hathaway as Kym, Rosemarie DeWitt as Rachel and Tunde Adebimpe as Sidney in 'Rachel Getting Married.'

Colorful, unconventional nuptial preparations serve as the backdrop for Jonathan Demme's "Rachel Getting Married," scenes somewhat reminiscent of "Monsoon Wedding" in their casual though sumptuous elaboration.

But while "Monsoon" was a comedy girded by serious undertones, "Rachel" is a raw and corrosive drama that dissects a young woman's war with addiction and her difficulties in dealing with the swirl of her sister's impending marriage.

It is one of the year's best independent films, lent immediacy and intimacy by hand-held camera work — there is, throughout, a sense of being a member of the party — and an ensemble-driven structure suggestive of a Robert Altman picture.

Finally emerged from the chrysalis of her adolescent roles, Anne Hathaway gives a searing performance as Kym Buchman, edgy child of a prosperous family, and an addict in shaky recovery. Her issues with soon-to-be-wed sibling Rachel (Rosemarie DeWitt), estranged mother Abby (Debra Winger) and father Paul (brilliantly played by Bill Irwin) obscure the root cause of her agony, a tragedy that director Demme and debut screenwriter Jenny Lumet (daughter of Sidney) take their time revealing.

The film unfolds over the course of a weekend in Connecticut, with two very different kinds of gatherings going on: people joined in the fun and folderol of the wedding party, and others caught in a quagmire of past events, struggling to draw strength from the parallel community.

A probing director, Demme wants to show (and generate) respect for the honesty of their emotions as well as their displays of self-delusion and courage. He succeeds.

Lumet's script is admirably devoid of formula or manipulation. She cares less about making her people likeable as she does about helping us understand them, so that in the end we are concerned with their fates. With rare exceptions, scenes that might have slipped into theatricality are instead shorn of histrionics. Kym may be a drama queen, but you believe every moment of it. There is humor in the story, to be sure, but it is just as often painful for the characters as it is a source of relief.

Hathaway, fragile, jittery and combative, does the most accomplished work of her young career (in what is admittedly a showy role). DeWitt's subtle portrait is one of the film's strongest and more nuanced. But the most impressive actor on view, arguably, is Irwin, who quietly, generously turns in a delicate balancing act of a performance, rich in emotion yet restrained.

The supporting cast, led by Winger, Tunde Adebimpe (as the groom) and Anna Deavere Smith as the sisters' stepmom, also delivers the goods. Among the principal pleasures of the movie is the wedding party's large and boisterous cast of friends and relations, assembled for an idyllic interlude of feasting, affection and music. And what music, a festive, multi-cultural score by Zafer Tawil and Donald Harrison Jr.

Production designer Ford Wheeler's lively sets couldn't be more engaging, and the photography of Declan Quinn, especially in close-up, does much to draw us in and enthrall the eye.

If there are quibbles with the film, they reside in overlength, and in the warm-and-cozy way in which it depicts this interracial marriage, with its breezy integration of black and white. Very appealing, and certainly possible, but perhaps a bit gauzy. It is the way race relations should be, and, sadly, so seldom are.

Reach Bill Thompson at bthompson@postandcourier.com or 937-5707.