There’s a scene in the upcoming indie dramedy “Goodrich” where Michael Keaton’s character, a Los Angeles art dealer lost in the weeds of a late-midlife crisis, agrees to attend a breath workshop to win over a New Age-y prospective client. As setups go, it’s something of a soft target: a fish-out-of-water Boomer, drowning in California woo-woo.

But the actor, his face a small hurricane of hope and anxiety, does more than find his “higher vibration.” He bobs and weaves and tries some kind of freestyle tai chi; he bats at a swarm of invisible bees and unleashes a primal scream (more like a strangled yelp, really). This is the Keaton that the “Goodrich” writer-director Hallie Meyers-Shyer envisioned when she conceived the screenplay.

“I wrote it 100 percent with him in mind,” she said, “to the point where if he had said no, I would have buried it and myself in the backyard.”

And it’s the same sense of unpredictability, a certain wild-card gleam, that has compelled the filmmaker Tim Burton to cast Keaton in five movies over nearly four decades, including, most recently, “Beetlejuice Beetlejuice.” “When you just look at Michael in ‘Beetlejuice’ or even ‘Batman,’ he has this sort of look in his eye,” Burton said. “That’s why I wanted him to be Batman, because you just look at him and go, ‘This is a guy who would dress up like a bat.’ You know what I mean? There’s something behind the eyes that’s just very intelligent, funny and dangerous and kind of crazy.”

The Keaton who settled into the corner booth of a hushed midtown Manhattan hotel lounge on a late-August morning didn’t seem like much of a maniac. Dressed in the dapper cool-dad uniform of fine-gauge knitwear and fitted slacks, he was still whippet-slim at 72 (he turned 73 on Thursday), and so soft-spoken in person that it was sometimes a strain to hear him over the cappuccino machine.