08/25/2011 08:46 am ET Updated Oct 25, 2011

HuffPost Review: Our Idiot Brother

Jesse Peretz's Our Idiot Brother is a summer-ending treat, a low-key comedy with sharp performances and a shaggy-dog feel.

It rises and soars on the wings of the performance by Paul Rudd as the title character: Ned, a second or perhaps third-generation hippie first seen selling vegetables from his commune at a farmers' market.

Ned is a trusting soul, so trusting that he lets the local cop - in uniform, no less - talk him into selling him a bag of weed. We next see Ned exiting prison, not noticeably sadder and, apparently, none the wiser.

And that's the central joke of Our Idiot Brother: That Ned is a positive-vibes kind of guy, someone who would never dream of thinking ill of anyone else. He assumes the same about everyone he meets: If you put out good vibes and expect people to return the favor, they will.

But the comedy arises from the fact that his three sisters - played by Emily Mortimer, Elizabeth Banks and Zooey Deschanel - are nowhere near as nice. Or they're living in denial. In either case, Ned is the force for good who triggers bad luck for each of them, because he assumes everyone approaches life the same way he does.

Initially staying with their mother at the family home on Long Island, Ned migrates to the homes of his sisters, one by one, each of whom hires him in some capacity in order to fulfill his parole requirement of holding a job. He starts with Liz (Mortimer), who is married to a snooty documentarian, Dylan (Steve Coogan). Ned is on hand to be Dylan's assistant and to serve as caregiver to their overly protected pre-K son. Ned shows him kung-fu movies and lets him eat sugar and other forbidden substances. He also discovers Dylan's little secret about the documentary that he's making about a lithe ballerina.

So he moves in with Natalie (Deschanel), who is in a lesbian relationship with a lawyer named Cindy (Rashida Jones) and living communally. But indiscreet Ned discovers Natalie's secret as well - so it's time to move onto the apartment of Miranda (Banks), a Vanity Fair reporter on the trail of a scoop about a party-set British royal (Janet Montgomery). Three is no charm - and so Ned spoils her life as well.

The plot is gracefully simple, with Ned's only love affair being with the dog, named Willie Nelson, he left behind on the commune with his ex, Janet (Kathryn Hahn, very funny as a passive-aggressive hippie). Ned is a modern-day Candide, who constantly has to be instructed by the people around him that he is far too trusting.

Rudd is a master at understated goofiness and brilliant at conveying optimistic vacancy. Cluelessness is one of his best comic modes and he gets an entire film to play a guy who isn't stupid or even dumb, just on a totally different page from everyone else.

Mortimer, Deschanel and Banks each have a different kind of energy that can't penetrate Rudd's sangfroid and thus leads to comedic short-circuiting on the women's parts. Coogan is savory as the documentarian poseur, while Sterling Brown has a delightful deadpan take on Ned's viewpoint as his parole officer.

"Our Idiot Brother" is a deceptively funny movie, one that never quite goes where you expect it to, utilizing farce constructs without every turning silly. It's smart comedy, something that is in genuinely short supply.

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