At one point late in The Past, a man walks into the hospital room of his comatose wife and asks her to squeeze his hand if she can hear him. It's a wrenching scene, one that lasts all of two minutes but makes every second count. Asghar Farhadi, who won the Oscar for Best Foreign Language Film two years ago with A Separation, has already shown he can mine the smallest moments for every bit of gut-punching drama imaginable. With his newest film, he all but perfects the art of making mountains out of molehills.

Few things are uncomplicated in Farhadi's movies, and here the Iranian writer-director devastatingly portrays the beginning of one marriage and the dissolution of two others. Before moving forward with their nuptials, an engaged couple (The Artist's Bérénice Bejo and A Prophet's Tahar Rahim) must sort things out with their respective exes and children. Neither is officially divorced, and their children are none too pleased with the situation. As suggested by the title and occasionally spelled out a little too bluntly by Farhadi—an early scene in which Bejo puts her car in reverse when she means to accelerate forward is the first of many reminders—these entanglements prevent everyone involved from either fully embracing the present or looking ahead to the future.

This thorny setup makes for a bracing, uncomfortable film that taps into the sort of raw emotions usually reserved for drawn-out confrontations rather than a night at the movies. Farhadi can put you in the room with his characters like few other directors, and the many shouting matches that erupt between Bejo and her daughter make you feel petty for even considering taking sides or passing judgment. You're inclined to give each the benefit of the doubt, even if you can't wait to leave that room.

Every conflict seems to get worse rather than better, as over the course of two hours Farhadi excruciatingly teases out the circumstances that led to Rahim's not-quite-ex-wife's coma. The revelations that follow may be melodramatic, but that doesn't make their impact any less visceral or awe-inspiring.

Critic's Grade: B+

SEE IT: The Past is rated PG-13. It opens Friday at Fox Tower.