What lies beneath the surface of life in a picturesque town, where mothers gather with their children at a neighborhood park, the town pool is the center of summer social life, and married couples lead what appear to be perfectly normal, happy lives with their families? What secrets hide beneath the facade of these seemingly idyllic lives? In Todd Field's Little Children, adapted with author Tom Perotta from his novel of the same name, people's lives intersect in unexpected and even dangerous ways, and nothing is quite as it seems.

Sarah (Kate Winslet) is a stay-at-home mom with an almost-PhD in English Lit. She is mired in deep unhappiness, almost an extended case of postpartum depression. Sarah chose to stay home with daughter Lucy, who is about three when we meet them, and she refuses to even consider child care; she's doing the stay-at-home mom thing, it seems, because it's the "right" thing to do, not because it's what she really wants. Sarah's depression and misery over the life she's found herself trapped in prevents her from really connecting with Lucy, this "unknowable little person" who is looking to her for love and nurturing. Sarah, to be blunt, is not good at the art of being a stay-at-home-mom -- and the other moms at the park let her know it in those subtle and insidious ways women use to attack each other.

The highlight of the moms' day is the daily arrival of The Prom King, a handsome, stay-at-home dad who brings his young son to the park. None of them ever actually talk to him or make him feel welcome, of course; he just serves as the fodder for their repressed sexual fantasies. One day, on a dare from one of the other moms, Sarah starts talking to The Prom King, whose real name is Brad (Patrick Wilson). On a sudden impulse, Brad and Sarah share a hug, and then a quick kiss -- scandalizing the other moms, who thereafter ostracize Sarah. Sarah, on the other hand, finds herself feeling alive for the first time in a long time.

Sarah and her husband Richard (Gregg Edelman) are not happy. Richard has become obsessed with the website of "Slutty Kay", while Sarah resents the freedom Richard has to go to work while she stays home. She counts down the minutes until his arrival each day like beads on a rosary, so she can escape the house -- and the omnipresent guilt of her lack of connection with her daughter -- for her nightly fitness walk. Brad, meanwhile, is unhappily married to Kathy (Jennifer Connelly), a sharp, sexy, domineering documentary filmmaker who supports the family while Brad tries (and repeatedly fails) to pass the bar exam. He has developed a sort of impotence over his failure to pass the bar that affects every aspect of his life; Brad is a man emasculated, subject to the dictates of his bread-winning wife on whether he can have a cell phone or subscribe to a magazine. Inevitably, Brad and Sarah are drawn together, and find in each other the support and understanding they lack from their spouses.

This storyline is carefully interwoven with another bit of drama affecting the town: The recent release from prison of a sex offender, Ronnie Mcgorvey (Jackie Earle Haley), who has moved into the neighborhood with his elderly mother (Phyllis Somerville). Brad's friend Larry (Noah Emmerich), a retired cop, has formed a "concerned citizens" group of one and launched an all-out attack against Ronnie, plastering the neighborhood with fliers showing the parolee's face and harassing Ronnie and his mother at all hours of the night.

Field weaves his storylines together slowly, taking his time building the relationship between Sarah and Brad, and not letting us in on the driving force behind Larry's obsession with Ronnie until almost the end of the film. The most remarkable thing about Little Children, though, is the way Field and Haley manage to create a sympathetic character out of a sex offender, without ever glossing over the fact that there's something very wrong with him. The film touches intellectually on the issue of revealing the identities of released sex offenders, and the fine balance between one person's right to privacy and the collective right of the community to be protected. Ronnie mostly seems to accept his fate as the town pariah; there's something wrong with him he can't control, and he wishes he hadn't been let out of prison to begin with. His deeply dependent relationship with his mother, though, and her unwavering love for her son even though he's done some "bad things," helps show another side of this pedophile, and humanizes him in an unexpected way.

What rings so true about Little Children is that it captures a slice of life that could be from anywhere, especially in smaller towns where everyone knows everyone else's business -- or thinks they do. At its heart, this is a story about the way we judge others, the way others judge us, and the way we judge ourselves. The acting is top-notch: Connelly brings just enough warmth to her icily domineering character to make you understand Brad's inner conflict over his relationship with Sarah; it's not so much that he doesn't want to be with Kathy, he just wants to somehow have back the relationship he and Kathy had before he came to see himself as a failure. Wilson, a Tony-award winning stage actor who won accolades for his recent turn in Hard Candy, captures the irony of Brad's dilemma, faced by a lot of stay-at-home dads: Does not being the one who brings home the bacon make a man somehow less of a man?

Winslet really shines here, as a beautiful, intellectual woman who has somehow lost her way on the road of life's choices and doesn't know how to find her way back to herself. Sarah is a character a lot of women will relate to, especially women who have given up professional careers to take on the life of a stay-at-home mom. It's hard to capture the loss of self-hood that can accompany that choice, but Field has written a character that feels very real, and Winslet, perhaps calling on her own experiences balancing the call of career with the pull of motherhood, captures the feelings to absolute perfection.

With 2001's In the Bedroom, Field showed his innate understanding of the way relationships work, and captured the essence of unbridled grief. With Little Children, he explores loneliness, judgment, and what makes us who we really are. As in In the Bedroom, about two-thirds of the way through the film, you start to wonder just how Field is going to pull everything together -- and then he does so with a shattering intensity that has you holding your breath in awe and anticipation. The film is perfectly paced, beautifully drawn and expertly acted. Field has a knack for putting slivers of life under a microscope and showing us the sometimes uncomfortable aspects of ourselves and our own lives, and Little Children makes us look more deeply into our own lives and ponder what's really going on under the surface. And that -- the ability to reflect life back at the viewer -- is filmmaking at its best.