In this film still released by Overture Films, Amy Adams, left, and Emily Blunt are shown in a scene from 'Sunshine Cleaning.'[Agencies]

It has become a genre all its own: the dysfunctional-family indie comedy, a staple of film festivals and art-house theaters alike.

Done wrong, and these movies can seem too self-consciously quirky (and by now, "quirky" feels like a word that was created especially to describe this kind of film). Done right, and you've got a "Little Miss Sunshine" or a "Juno" on your hands.

"Sunshine Cleaning" falls into the latter category — and its producers happen to have been behind "Little Miss Sunshine," as well. Both films share an Albuquerque, N.M., setting and Alan Arkin as a lovably outspoken father and grandfather. But really, that's where the similarities end; despite its perky title, "Sunshine Cleaning" is much darker as it ventures simply and realistically into suicide, adultery and loss.

Amy Adams and Emily Blunt have great chemistry as Rose and Norah Lorkowski, underachieving sisters who stumble into the crime-scene cleanup business. Once a cheerleader at the height of her high-school popularity, thirtysomething Rose now finds herself a single mom working as a maid, which sometimes requires her to clean her former classmates' McMansions. Younger sister Norah is even more of a screw-up, partying hard, getting fired from waitressing jobs and still living at home with dad (Arkin).

All that changes — somewhat — when Rose's married lover (Steve Zahn), a cop, suggests that she step into the lucrative world of mopping up messy crime scenes. Rose is immediately intrigued by the prospect: She needs the extra money to put her highly imaginative but misunderstood son, Oscar, in a private school. (Young Jason Spevack's performance is blissfully free of precociousness.)

Rose recruits her unemployed sister, but Norah isn't quite so enthusiastic about washing blood from murder scenes and airing out trailers that reek of decomposing corpses — that is, until she finds an unexpected connection with the daughter of one of these victims, played by Mary Lynn Rajskub of "24" in a subplot that feels underdeveloped.

But the overall lack of sentimentality in first-timer Megan Holley's script and straightforward direction from Christine Jeffs keep the film from becoming too predictably feel-good; at the same time, the strong performances help elevate among similar fare. Adams and Blunt have a subtle and believable sibling dynamic; while Adams has been best known for engaging, energetic roles in films like "Enchanted" and "Doubt," here she allows the weightier side of her talent to emerge, which makes her seem like a grown-up for the first time. The always-alluring Blunt, meanwhile, continues to show her versatility.

Clifton Collins Jr. is lovely in just a few scenes as the gentle soul who runs a cleaning-supply store (and thankfully, "Sunshine Cleaning" doesn't force his presence as a potential love interest for Rose). And Arkin is a cantankerous hoot in a role similar to the one the earned him a supporting-actor Academy Award for "Little Miss Sunshine": a widower peddling various products from the trunk of his junker car and doling out half-baked advice to his grandson.

Turns out the business of death forces them all to figure out what really matters in life.

"Sunshine Cleaning," an Overture Films release, is rated R for language, disturbing images, some sexuality and drug use. Running time: 98 minutes. Three stars out of four.

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