Chris Rock delivers something unexpected with his fourth feature as writer-director, Misty Green, a slice-of-life movie that doubles as a bitter kiss-off to Los Angeles and a ride through the hellscape of working in Hollywood, seen through the titular actress as her once-promising career flickers out. But the surprise isn’t the harshness of Rock’s look at modern L.A., or that the beloved comic, who built his name on real talk about race and politics, would center the film on this woman. It’s the stunning performance he draws from British actor Rosalind Eleazar as the salty, self-sabotaging, washed-up Misty.

Before this starmaking turn, Eleazar built a stateside profile on Apple TV’s Slow Horses alongside Gary Oldman and Kristin Scott Thomas. She spent four seasons on the critics’ darling as Louisa Guy, a disgraced, mourning MI5 agent. Before that, she appeared in the BBC’s Howards End as Jacky Bast, and in between these prestigious TV roles she worked on English stages, having trained at the London Academy of Music and Dramatic Art.

That varied résumé was a fitting prelude to Misty Green, a chaotic drama that’s messy, complicated and unapologetic, just like the one-time starlet it follows for a week or so as she moves through Los Angeles watching her life unravel.

“She’s so incredibly complicated and contradictory, and you know she’s difficult to get on board with, because she’s so self-destructive,” Eleazar told the audience at this year’s New York Film Festival, where the film premiered this month. “But I have a lot of compassion for people that sort of go out into the world with so many layers of protection. Because they’ve experienced so much hurt and so much pain that they’re constantly fighting, and it’s not necessarily pleasant to be around. But those are the sort of characters that make you want to unpack and figure out what, like, what is it? What makes her go out into the world with such a fierce exterior.”

Over just under two hours, Rock searches for what’s behind Misty’s destructive streak as, on the cusp of losing her housing, she escalates the damage she does to herself. She tells off her agent, then tries to seduce him. She runs into industry types she still resents and has frank conversations with a fellow has-been starlet (Anna Kendrick, doing great work). Then comes a reckless, cocaine-fueled night of sex in a restaurant bathroom with a longtime “friend,” played against type by Adam Driver. (The film makes clear they’re not real friends at all.) It sends her down her darkest path yet.

The decision Misty makes as the film enters its third act is partly precipitated by her bipolar kind-of brother, her lone touchstone to a troubled childhood that’s kept frustratingly vague. As played by the great Daniel Kaluuya, he gives some initial hope that Rock is about to offer a cutting portrait of the mental health crisis among Black Americans. Unfortunately, like the plundering of his heroine’s psyche, it falls by the wayside, and the brother’s story is shoehorned into an unnecessary serial killer subplot.

With occasional photo montages suggesting the perpetual problems of modern L.A., the film is also teeming with characters who fit the most blasé perceptions of Angelenos. Rock clearly has something to say about the city, and it ain’t nice. At NYFF, the comedy icon clarified his beef.

“L.A. is America in a way,” Rock told the crowd at Lincoln Center. “It’s the best of times. It’s the worst of times. It’s the weather and the palm trees and homeless people everywhere, man. Just like, Magnolia. It’s like wow — Skid Row and Rodeo Drive are seven miles apart. So I try to capture all of that.”

Rock, who drifts in and out of the film as a filmmaker, a phantom from Misty’s past and a potential lifeline to a Hollywood future, has been established for more than three decades. His astute stand-up and withering, spot-on insights into race, relationships and celebrity have influenced countless comedians and writers.

As a director, he has made just four films: the comedies Head of State, I Think I Love My Wife and the critical hit Top Five, and now Misty Green. He has described the new one as about the “soul-sucking” nature of Hollywood and who gets redemption. That’s what Misty is seeking throughout, whether she realizes it or not.

“I always felt that acting isn’t the right profession for Misty; even though you’re talented at something, it doesn’t necessarily mean that that is the right profession for you,” Eleazar said. “And I think for someone who has her own mental health issues and is also a functioning addict, she actually needs a job that provides a routine, and she needs a slightly smaller life, and a life that’s going to give her a bit of peace.”

At the premiere, Rock offered a related thought.

“It’s important to live in the now,” he said. “It’s that weird thing when you get success at something, especially the way show business is set up right now. You can talk about something you did 30 years ago for a long time. You can do that, but some people have worked, and some people need to live now.”