Wife-swapping, a decidedly swinging '60s activity, seems to be all the rage once again.
First came the Fox reality series "Trading Spouses" and ABC's upcoming "Wife Swap." Those focus on the innocent, fish-out-of-water laughs that result when two moms trade places and take the heat in somebody else's kitchen.
Now comes "We Don't Live Here Anymore," which goes in the bedroom - and that's only sort of a pun. The film is based on two short stories by Andre Dubus, whose writing also was the basis for "In the Bedroom," the best movie of 2001 (at least according to this critic).
Like that earlier film, "We Don't Live Here Anymore" potentially could have been soapy, but its intelligent dialogue, raw emotions and nuanced performances from a strong cast manage to elevate it.
A somber, updated version of "Bob & Carol & Ted & Alice," "We Don't Live Here Anymore" stars Mark Ruffalo and Peter Krause ("Six Feet Under") as Jack and Hank, appropriately rumpled college professors and best friends living in a small, woodsy town. They get together often for dinner parties with their wives - Jack is married to Terry (Laura Dern) and Hank is married to Edith (Naomi Watts) - and their evenings have an idyllic, inebriated glow.
After drinking too much gin one night, Terry notices that Jack and Edith find reasons to sneak off together - for beer runs, for example - and confronts him in a rage once they get home, where their young son and daughter are trying to sleep upstairs.
And she was right, but she doesn't know it yet: After surreptitiously eyeing each other, Jack and Edith shared a passionate kiss in the convenience store parking lot. But she's far more forthcoming than her husband when she admits that Hank hit on her while their spouses were away.
Not only is Jack not shocked by this revelation, he actually feels some screwed-up sense of relief as he launches into his own affair with Edith.
And Edith, whose tidy home provides a marked contrast to the perpetual mess of Terry's, is just as practical about their relationship. "I wonder how we'll get caught," she wonders matter-of-factly after one of her naked romps with Jack in the woods.
Hank, meanwhile, is more concerned with agonizing over his novel than paying attention to his wife and daughter. With the complacent swagger of a guy who knows he's good-looking, his motto is: Love your wife and kids but have sex with as many other women as you can.
Director John Curran doesn't judge any of the characters for their actions (or inaction), especially as each member of the philandering foursome begins to realize exactly what everyone else involved is doing.
That you want to see Jack and Edith not get caught - that you want them to revel in the joy of being discovered anew and the liberating thrill of the wrongness - is a testament to the actors' chemistry and the complexity of Dubus' words, as adapted by screenwriter Larry Gross.
Hank and Terry aren't as fully developed as Jack and Edith, and neither is their affair - perhaps because the short stories on which the film is based are told from Jack and Edith's perspectives.
But Dern does get to go on some showy, drunken tirades, reminiscent of Elizabeth Taylor in "Who's Afraid of Virginia Woolf?"
Ruffalo's part is the most multilayered, requiring him to be passionate, furtive, angry and vulnerable, all of which he accomplishes masterfully. This year alone, he's proven he can do anything: from light comedy ("13 Going on 30") to action ("Collateral") to a surreal adventure from screenwriter Charlie Kaufman ("Eternal Sunshine of the Spotless Mind"), which defies categorization.
And Watts continues to show the versatility that characterized her powerful performances in "Mulholland Drive" and "21 Grams," flashing believably between ardor and remorse, sometimes within the span of a single glance.
"You love the person you're having the affair with," her character says - an insight that undoubtedly will alienate some viewers, but is emblematic of the fearlessness with which the film covers complex emotional territory.
"We Don't Live Here Anymore," a Warner Independent Pictures release, is rated R for sexual content and language. Running time: 103 minutes. Three stars out of four.