Lisa Cholodenko is an uncommonly gifted writer/director, skilled at crafting potentially shallow situations, then giving them life and depth with her perceptive dialogue and characterizations. In the hands of a lesser filmmaker--a Nancy Myers, say, or a Brian Robbins--The Kids Are All Right and its story of a lesbian family shaken up by the presence of their long-ago sperm donor might not rise above the level of a slightly bawdy sitcom. But Cholodenko sees more layers than that; she understands these characters, knows them--their histories, their secrets. Some of these people are types, but--here's the key--they don't know that. And Cholodenko does, though she never treats them that way.

As the story begins, Joni (Mia Wasikowska) has just turned 18. A straight-A student on her way to a good school, she's the pride of her "unconventional" family; she has two moms, Jules (Julianne Moore) and Nic (Annette Bening), and a brother, Laser (Josh Hutcherson)--a half-brother, technically, since each mother gave birth to one of the kids. But both Joni and Laser came from the same sperm donor, and now that Joni's 18, Laser is pushing her to track the guy down. Joni's not so sure; the family's reasonably happy, as far as those things go, though there seems to be a lot of dinner table tension between the moms lately.

But she finds the guy. His name is Paul (Mark Ruffalo), and he's a good-natured, laid-back restaurant owner; he's got the kind of upscale California spot where the tables are mostly outdoors and the veggies come from the nearby cooperative organic garden. (Cholodenko's peerless sense of place is even more finely tuned here than it was in her brilliant 2002 effort Laurel Canyon.) Joni and Laser are awkward around Paul at first, but they take a liking to him (he's likable as all get out); soon enough, the moms find out what they're up to and insist on meeting him too. And that is when things get complicated.

When they do, it's in smart, believable ways--infractions large and small start to fester, and little things become big problems. Paul isn't the cause of all of the damage he eventually wreaks, not necessarily; he's more of a tremor that knocks their foundation off-balance. In the first half or so, Cholodenko's deceptively simple screenplay traffics heavily in the comedy of awkwardness; it's real, not mannered or forced, but it feels like a choice. ("Feel free to ask me anything you want," Paul tells the kids when they first meet. "Great!" Joni replies. Long pause.) Later in the film, we see what she was doing in those pauses, how loaded they are--they're the subtext that gives the eventualities their poignancy. As the five of them gather for dinner at Paul's and we watch them interact, we find ourselves wound up tight in their predicament--and the specific way in which we're put right into Bening's head at the toughest moment of the night is skillful, surprisingly visceral filmmaking.

Which is not to say that The Kids Are All Right is serious business--quite the contrary. Cholodenko has a light, elegant comic touch, a jazzy way with fast dialogue, and a sharp comic sensibility; she finds laughs in the lines, in the pauses, in the reactions (the cutaways to Moore during the Joni Mitchell sing-along are priceless), sometimes even in the edits. There's a broad, semi-slapstick bit with a remote and a porno movie towards the beginning, and damned if she doesn't pull it off like a pro. But it's never just funny; even the throwaway bits resonate afterward.

Bening and Moore are, simply put, fantastic together; there's richness and history in their interactions, in the ways that they poke at each other, in their knowledge of each other's hot buttons. Both transcend the potential landmines of their characters and situation--at first glance, they're easily summarized (Bening is the type-A professional, Moore the aging hippie butterfly), but the more time we spend with them, the better we understand how they've allowed themselves to both put each other into those boxes and to be put into them, and how they're both comforting and hurtful. Both actors get the opportunity to do what they do best--Bening exhibits her arid-dry wit, Moore her earthy charisma--and then to push themselves into trickier places. By the end of the film, when Moore shuts off the TV and apologizes to the family, she gets at something real and moving and kind of miraculous, and Bening wrecks you just by the way she listens.

But Ruffalo shines brightest. Again, the character could be played as a caricature, the easy-breezy aging hipster, not too bright, but not a fool either. Ruffalo pins the characterization down early and never hits a false note; he's the guy who's made being oblivious a lifestyle choice. There's one quick moment where the actor and director tell us absolutely everything about the character: when he and Moore cross a line and she flees, the camera lingers on him for just a moment, and we realize from his giddy reaction that he has no idea what he's just stepped into. That kind of childlike, Katy-bar-the-door enthusiasm can do far more damage than a comparable serving of bitter malice, because he's entirely ignorant of the stakes. As an actor, Ruffalo is doing something really complex that looks crazy simple. It's a clean, funny, complicated piece of work.

Cholodenko's timing is occasionally off--some scenes go on a beat or two too long, and the conflicts with the kids late in the movie are a bit predictable, lacking the complexity so present in the rest of the story, slathered in the bland score by the usually-reliable Carter Burwell. No matter; Cholodenko finds just the right for each and every scene, and holds it for as long as possible. The Kids Are All Right is wonderful.

Jason lives in New York. He holds an MA in Cultural Reporting and Criticism from NYU.