Mr. Zvyagintsev said he first sought to make a Russian version of Ingmar Bergman’s searing “Scenes from a Marriage.” When he could not secure the rights, he and Oleg Negin, his longtime writing partner, found inspiration in a news report about a missing persons nonprofit, unusual for Russia in its effectiveness, and combined that with the drama of a family rotting from inside.

Production proved almost as hair-raising as the script. Set in the fall, filming had barely begun in October 2016 when snow blanketed Moscow and stayed. The director was forced to recreate autumn during the spring thaw, using stored leaves.

Two key scenes, about 15 minutes in total, were missing when Mr. Zvyagintsev submitted the film to the 2017 Cannes Film Festival. He shot the last scene three days before the festival announced that it would include the movie. He edited the final version in roughly a month.

“Those were extreme circumstances,” said the soft-spoken director, sitting in a small Moscow cafe a day after a 12-hour flight from Los Angeles. He had not shaved; his eyes were alert behind black glasses, but accented by dark circles. His dark hair cropped short, he wore a bulky black turtleneck sweater flecked with multicolored dots.

“Loveless” won a Jury Prize at Cannes last May, and the director has been on the road selling it ever since.

Mr. Zvyagintsev, 54, set out to become an actor.

Born in the Siberian city of Novosibirsk, he was 4 when his parents announced that they were splitting up and his father looked him in the eye and asked him to choose a parent. (He insisted that this did not inform the devastating scene when the audience understands that Alyosha knows that he is not wanted.)

His mother, a Russian literature teacher, proved to be the right pick, he said: She always supported his choices, whereas his father, showing up just a few times, banged on the table and yelled when he discovered that his adolescent son was in theater school.