Every movie is a chemistry experiment, and “Everybody Knows” does a clever thing with the chemistry between its two Oscar-winning stars.

Penelope Cruz and Javier Bardem made their first movie together in 1992, and have been married for about a decade. They have, to put it mildly, chemistry.

“Everybody Knows” casts them as former lovers, characters who grew up together and had a torrid relationship in the past, but are now married to other people. They still feel something for each other, of course. So all that chemistry has to be throttled, which creates a simmering heat to their scenes together.

This works for the movie, because “Everybody Knows” is all about unspoken resentments and unaired grievances. It’s a typical moral quandary from the mind of writer-director Asghar Farhadi, the Iranian filmmaker whose “A Separation” and “The Salesman” each won Oscars for Best Foreign Language Film.

Here, Farhadi moves his story to lush Spanish winemaking country. Cruz’s character, Laura, now lives in Argentina but returns home for a family wedding. Shockingly, on the night of the celebration, her teenage daughter (Carla Campra) is kidnapped.

The members of the extended family take it upon themselves to search for answers. This includes Paco (Bardem), Laura’s ex, whose is now happily married to Bea (Barbara Lennie, fierce when she needs to be); they own a vineyard and work the land themselves.

The situation is tricky. As Paco is rudely reminded, he was a servant in the family household as a child, and is considered lower class. Yet he’s the only person who might be able to come up with enough money to pay the ransom.

Other family members have money problems, which raises suspicions. And when Laura’s husband (South American star Ricardo Darin, from “The Secret in Their Eyes”) arrives from Argentina, he also admits his bankruptcy.

The movie scatters red herrings around: Like any good mystery, we’re meant to wonder whodunit.

So it’s manipulative at times. But Farhadi’s real focus is not so much the crime as in how people treat each other, and the hypocrisies this family has maintained to keep itself going.

On that score, “Everybody Knows” is fascinating. It’s also a feast of great actors. Even the small roles ring true; Jose Angel Egido is especially fine as a former cop who seems to see through each character as soon as he meets them.

Cruz is believably grief-stricken, and Bardem really gets to stretch out as an earthy self-made man, a Zorba the Greek type forced to re-assess his existence. It’s an expansive turn full of zesty physical presence and small psychological shifts. Like the wine this film keeps returning to, both actors are aging well.

“Everybody Knows” (3½ stars)

A dense psychological study wrapped inside a kidnapping plot: In Spanish winemaking country, suspicion falls on various members of an extended family when a teenage girl goes missing. The film is meticulously directed by Oscar-winner Asghar Farhadi (“A Separation”), and Penelope Cruz and Javier Bardem lead an excellent cast. In Spanish, with English subtitles.

Rating: R, for violence, subject matter

Opening Friday: SIFF Uptown theater