The stubbornness of love is the subject of “Birth,” a moody new film with a committed Nicole Kidman performance. At first glance, the movie’s subject sounds like another dumb variation on “Big” or “13 Going on 30,” but the idea here is more serious.

An eerie prologue shows a jogger dropping dead in the snow of Central Park. Then we skip ahead 10 years. The dead man’s widow, Anna (Kidman), is announcing her engagement to a successful man, Joseph (Danny Huston, star of “Silver City”).

One night, as Anna and Joseph are enjoying dinner with her family in the ritzy apartment owned by her mother (Lauren Bacall), a 10-year-old boy quietly slips into the place. He asks to speak with Anna, and calmly informs her that he is the reincarnation of her dead husband.

Over the next few days, the kid (whose name is Sean, like the late husband’s) keeps insisting he is married to Anna. His parents scold him, Anna discourages him, and Joseph threatens him. But he insists.

Anna can’t dismiss this absurd situation. She invites Sean to stay at the home. She questions this grave little 10-year-old about women. “You ever made love to a girl?” she says. “You’d be the first,” he evenly replies.

Director Jonathan Glazer (“Sexy Beast”) doesn’t shy away from the weirdness of this situation. In one scene, Sean surprises Anna taking a bath, and gets in the tub with her.

It’s clear that Anna’s grief is so real, she’s willing to consider the unlikely possibility that Sean might really be Sean. In an interesting way, “Birth” is about the way people in love see what they want to see, and believe what they want to believe. Anna’s dilemma is just an exaggerated version.

Glazer wrote the script with Milo Addica and Jean-Claude Carriere, the Frenchman who has his name on more great scripts than perhaps any other writer. The muted, sculpted photography is by Harris Savides. While the movie is perhaps overly polished (Glazer is a TV commercial director), a subterranean vein of humor keeps it fresh.

Nicole Kidman brings her usual laser-beam intensity to the role (which is only accentuated by her close-cropped hair). There’s a scene at the opera, after Anna has first met the 10-year-old pretender, where the camera focuses on Kidman’s face for a very long close-up. She brings the moment off.

The boy is played by Cameron Bright, who was the creepy kid in “Godsend.” Anne Heche and Peter Stormare are touching as friends of the dead husband, and Cara Seymour and Ted Levine fill out small parts as Sean’s parents.

“Birth” sneaks up on you, in a very specific, uncanny way. It doesn’t have much flash, in what is about to become a busy holiday movie season, but it’s worth seeking out.

Danny Huston, Cameron Bright and Nicole Kidman in “Birth.”

“Birth” HHHH

Surprising: A 10-year-old boy presents himself to widower Nicole Kidman, claiming to be the reincarnation of her dead husband. This peculiar situation prompts a meditation on the meaning of love, with an intense performance by Kidman carrying the day.

Rated: R rating is for nudity, language, subject matter.

Now showing: tk

“Birth” HHHH

Surprising: A 10-year-old boy presents himself to widower Nicole Kidman, claiming to be the reincarnation of her dead husband. This peculiar situation prompts a meditation on the meaning of love, with an intense performance by Kidman carrying the day.

Rated: R rating is for nudity, language, subject matter.

Now showing: Grand, Meridian 16, Metro.