Not much happens plot-wise in “Christmas Eve in Miller’s Point,” the third theatrical feature from Tyler Taormina, but it has, as they say, a lot going on. In this ensemble comedy, centered on the Christmas gathering of a family so large that theaters ought to hand out a genealogy chart, the movie is at once hyper-specific about place — western Suffolk County on Long Island — and intriguingly loose about time.

Scored to a soundtrack of early-1960s hits, the film is set in the aughts, judging from the dialogue, the cellphone technology and the TV (with its built-in DVD and VHS players) on which some of the kids play video games. The details (a player piano, cherry affogatos for dessert) are quirky enough to feel remembered, and Paris Peterson’s production design makes the home look lived in. The scant overt drama involves disagreement among siblings about how to handle their mother’s decline and whether to sell the house.

Those siblings include Kathleen (Maria Dizzia), whose daughter (Matilda Fleming) is giving her attitude and whose husband (Ben Shenkman) awkwardly tries to fit in, and Ray (Tony Savino), who is secretly writing a novel. A cousin, Bruce (Chris Lazzaro), is a firefighter who is cheered on by the others when he rides by on a festively decorated truck. Somehow the film finds roles for not one but two adult children of auteurs, Francesca Scorsese and Sawyer Spielberg — though not as relatives, alas.

As in his earlier features “Ham on Rye” and “Happer’s Comet,” Taormina gestures toward the surreal, especially once he steps outside the main location. Two police officers (Michael Cera and Gregg Turkington) spend much of the movie in stone-faced silence; their New York City uniforms suggest that they’re operating out of their jurisdiction. “Miller’s Point” is a Christmas movie more invested in atmosphere, and the qualities of wintry light, than in holiday cheer — and that somehow makes it all the more warm.