Timothée Chalamet Is Uncanny as Bob Dylan

In one of the many incandescent, finely layered scenes that make up “A Complete Unknown,” James Mangold’s entrancingly offbeat drama about the early years of Bob Dylan, we watch Dylan (Timothée Chalamet) and Joan Baez (Monica Barbaro), who’ve been involved musically and romantically, perform a duet at the Newport Folk Festival in 1964. They’re singing Dylan’s “It Ain’t Me Babe,” and the way their voices blend (their smiles too) creates a sound so pure it feels sunlit. Mangold lets the song roll on in its entirety, as he does with many of the songs in “A Complete Unknown,” so that they literally become the story the movie is telling.

This number is like a shimmering dream, but part of it is the drama that’s unfolding beneath. Baez, at this point, has had it with Dylan. He’s a moody, self-absorbed folk celebrity hipster poet, always placing himself at the center of things (yet somehow always looking like he’s too cool to be there). And since Joan herself, with that quavering soprano, is a fierce customer, famous in her own right, she’s done with being treated like Dylan’s accessory. The song they’re singing expresses how they feel about each other (“It ain’t me, babe,/It ain’t me you’re looking for, babe”). Yet they invest it with so much passion that it sounds like a romance. (Bob’s other girlfriend, played by Elle Fanning, gets so caught up in the singers’ connection that she turns away from the stage in tears.) Folk music is rooted in a devotion to the world, but at that moment what Dylan and Baez are singing about is devotion to the self: the new world that’s coming. That’s why the scene makes your heart burst and your head spin at the same time.

“A Complete Unknown” is a drama of scruffy naturalism, with a plot that doesn’t so much unfold as lope right along with its legendary, curly-haired, sunglass-wearing coffee-house troubadour hero. Yet the feel — the effect — is that of a…