The opening 10 minutes of Marriage Story are two voice-over monologues with accompanying imagery — one by Nicole (Scarlett Johannson), an actress, and one by her husband Charlie (Adam Driver), a New York theater director — that are joyous recollections about what each loves about the other: What a good parent they are, or how talented, or how they fill in the gaps of the relationship. They seem like a happy couple.

But it turns out to be a bait-and-switch: We quickly find that these are lists each has been assigned by a mediator to help transition them through their pending divorce. After nearly a decade, they have grown apart, and have different goals, but they still love each other, still want to be friends, don’t want to get lawyers involved.

This sad development is couched in good news for both — Nicole has been cast in the lead of a TV pilot shooting in L.A., and Charlie has won a MacArthur Foundation “genius” grant. But even those bright spots cause friction in ways nobody but the audience can foresee, exacerbating tensions in the relationship, providing leverage in negotiations and turning this amicable separation into a fierce battle that neither really wants to engage in, but each is powerless to alleviate.

If you see an overt irony in naming a movie Marriage Story when the marriage is all but over at the start and the thrust is divorce, you’ve missed the searing, touching, intelligent complexity in writer-director Noah Baumbach’s beautifully bittersweet valentine. Even though clearly inspired by his own life (Baumbach was once married to actress Jennifer Jason Leigh), it’s not a revenge picture against a shrill ex-wife. Neither does it zing along as an exaggerated farce like The War of the Roses or Mr. and Mrs. Smith, or tell one side the way Kramer vs. Kramer did (though brilliantly). Charlie maybe even comes off worse, though your loyalties pendulate — how much does Nicole’s decision not to participate actively in the mediation set them down the wrong course? Why does she see a lawyer on the sly? Why does Charlie escalate? How can he not see how naive he was thinking she would move back to NYC with their son? But rather the come across as literary hurdles conjured by a screenwriter, the developments seem entire driven by character. We learn bits about each party, good and bad, in pieces. Their frustrations are ours.

And they are magnificently conveyed not just by Baumbach, but by the actors. Johansson is the first to wow us: In an early scene where she tells her new lawyer (Laura Dern) about the troubles in her marriage, she wanders around an office in one long take, modulating her emotions and hitting each line with remarkable ease. It’s a shining moment, akin to Emma Stone’s audition scene near the end of La La Land

But Driver eventually matches her. I’ve always liked but never loved Driver; he’s odd looking and can be dour. Here, that dourness is used to full, especially in the “home visit” scene by a social worker and a moment where he sings Sondheim’s “Being Alive” (the second song from Company performed in the film — a smart nod to the emotional backstory). You’ll fall in love with his performance. And when the two finally “have it out” … well, remember the climactic scene between Tony and Carmela at the end of Season 4 of The Sopranos? … This is better: Savage, heartbreaking, honest. (Dern, in a potent supporting role, does gangbusters as well.)

Marriage Story skirts a razor edge in tone, never seeming mawkish, mean, melodramatic or flippant. Its power is in its authenticity, and it’s one of the best movies of the year.

— Arnold Wayne Jones

Opens Friday in theaters; debuts on Netflix Dec. 6.