"We Need to Talk About Kevin" is every neurotic parent's nightmare. In writer/director Lynne Ramsay's stomach-knotting domestic horror story, Tilda Swinton is Eva, a free-spirited travel writer who feels a worrisome lack of mothering instincts when her firstborn son arrives.

The child makes her heart ache, but not with love. For all her strained efforts at bonding, she can't connect with the squalling, fussy, misbehaving infant, and he has an instinctual aversion to her. Rearing him is soon an unwelcome chore that grows worse as the years pass. We tour Eva's troubled memories over the next two decades through non-chronological, stream-of-consciousness puzzle pieces that drip menace from every frame.

There is a dark music in this film's language. We meet Eva in a good-old-days prologue, reveling in an exuberant, squishy food fight at a Spanish tomato festival. Ramsay shows us the scene in slow motion, giving the colorful, sensual images a flavor of foreboding. Then we flash forward to see Eva as a pariah, living alone in a small bungalow littered with wine bottles and spattered by vandals' red paint. There are scenes of her marriage to easygoing, prosperous Franklin (John C. Reilly), who provides every material comfort but scant emotional support.

The trajectory of the story is Eva's downfall, as Kevin's emotional stranglehold tightens like a garrote. Putting Eva in ever shabbier, more confined surroundings, Ramsay makes sure we feel the noose around our throats, as well.

Eva tries to forge a connection with Kevin, but those gestures prove as futile as her effort to will tenderness into her own heart. Kevin grows from a detached, malicious, antisocial toddler to a manipulative, malevolent teen, whose life's mission is tormenting his mother. He feigns love for his clueless dad and little sister so that when Eva brings up Kevin's lack of empathy, no one understands. Surely that terrible incident with the drain cleaner must have been accidental? And Kevin's obsessive interest in archery -- well, every boy needs a hobby.

Ramsay uses every article of film vocabulary to chilling effect. You've never heard Buddy Holly's chipper "Everyday" sound so ominous. But it's the cast that overshadows all; it's hard to praise the acting in this film adequately. Swinton's richly layered performance is a master class on emotional transparency. Her every skirmish with guilt, doubt, dread and (brief, unwarranted) relief is painfully real.

The part of Kevin is brilliantly cast three times over. Young Rock Duer plays the boy as a toddler, Jasper Newell is the preadolescent and Ezra Miller is the calculating, malevolent teen. The actors are a perfect match physically, and they project the bad seed's soulless, half-amused hatred chillingly. Miller is simply diabolical; he makes the cataclysmic finale seem simple and inevitable.

Eva grows sick with fear that she bears some responsibility for the devil-child her son has become. A modern, self-sufficient, globe-trotting career woman before parenthood, she is a virtual prisoner at the end. Is she the bearer of guilt? The victim? An innocent bystander? It's a hallmark of "Kevin's" emotional bravery and intellectual honesty that the questions haunt us long after the end credits roll.