In fall 2017, something odd happened to Fredrik Backman, the bestselling Swedish author of 2012’s A Man Called Ove. He was scheduled to be at a book fair in Copenhagen, but suddenly nothing made sense. “All the dates were confused, I didn’t know where I was supposed to be,” the 39-year-old says via WhatsApp from his home in Stockholm. “There’s an expression in Swedish when you’re burned out. They say, ‘This person hit the wall.’ That’s what I did.”

Backman’s wife and his agent, he explains, “shut everything down.” He took a break from book promotion and started working with a psychiatrist. “I’ve always struggled with anxieties,” he says. “I’m a pretty anxious person. That’s one of the basic traits needed to become a writer.”

In fact, Backman had turned to therapy 15 years before, after he was shot in the leg during a robbery, which left him on crutches and “scared of everything,” he says. “My wife will look at me and say, ‘Strange things happen to you. These things happen to you a lot.’ ”

Backman pulled from both of those moments for Anxious People, his latest novel, which is set for a September release in the U.S. from Atria Books, his longtime American publisher. The story involves a failed bank robber who takes hostage a disparate group of people—including a young lesbian couple, a wealthy bank director, an elderly woman, and two middle-aged, married house-flippers—at an open house. The cops who investigate the situation, a father and son duo, soon realize all is not what it seems.

Each character has a story that slowly unrolls, revealing a complicated, heart-rending, tragic, hilarious, and interconnected truth. “I steal little things from a lot of people, and I pour that into a character until that character is real for me,” Backman says. “I care about this person, and at that point it works.”

Sometimes Backman steals from himself, like in the scenes where one character sees a therapist. “The psychiatrist being annoyed with this narcissistic person comes from me,” he says.

In Backman’s case, what came from hitting the wall was wanting to write about anxiety. “But not people in an extreme situation,” he says. “Normal people living with anxiety and trying to cope, people who are feeling like, ‘I’m just trying to get through the day here.’ ” He wanted to write about the feelings he himself had experienced—that sense of failure and futility that can happen regardless of success.

Backman knows about failure and success. After being rejected by multiple publishers in Sweden, A Man Called Ove went on to sell more than 2.8 million copies in the U.S. alone, and the paperback spent 90 weeks on the New York Times bestseller list. According to Atria, his books have sold more than five million copies across all formats in the U.S., with 12 million copies sold globally.

Almost all of Backman’s books touch on suicide, and in Anxious People a man jumping off a bridge has a far-reaching effect. For Backman, who’s struggled with anxiety as well as depression, this is personal. “I had a very close friend who ended his life when I was about 20 years old, and that never stops affecting you,” he says.

Parenting is another recurring theme in Backman’s work. He’s fascinated by “the really stupid things you do for your kids because you’re a moron,” he says, adding, “We‘ve had kids since the beginning of human evolution, and we still don’t know how to interact with them.”

Anxious People grapples with both mental health and parenting, but at its heart it’s about how we are all connected. “A person standing on a bridge—that story affects a lot of other people,” Backman says. “That’s the furthest edge of the anxiety I’ve struggled with. I wanted to write about that and how what you do and don’t do actually matters. People will have to deal with your choices for the rest of their life.”

When Backman begins a book, he tries to create as small a world as he can—A Man Called Ove unfolds, basically, on one street—so he can delve into the human emotions there. In the case of Anxious People, he and his wife had been going to a lot of open houses, where he quickly found himself looking at people, not real estate.

“I had the idea that this would be a really fun setting for a hostage situation,” Backman says. “You walk in; you’re enemies with everyone. All of these people are in competition. And all of these people are very anxious.”

Backman notes that house hunting, after all, tends to bring out a host of existential questions: “Is this where I want to live? Is this how I view myself? Can I afford this? Do we want to have kids? What kind of parents would we be? In the next five, or 10, years, where do we see ourselves?” It’s a reflective take on the future from someone who says he never thought much about what he’d be when he grew up. “[I wanted to be] a soccer player when I was really little; then you get older and realize, ‘I have no talent at all!’ ”

In adulthood, Backman’s gigs included being a forklift driver and a blogger. “I still don’t feel, ‘Oh, I’m an author,’ ” he says. “If these were medieval times, I would be the guy wandering from village to village telling stories for coins.” It’s pretty much the only thing he’s been doing since the age of 25, but he still assumes it could all go away tomorrow. “The only thing that people have to decide is, ‘We’re done with this,’ and that part of my life is over. But I’ll still tell stories. I don’t have much in the way of hobbies. I don’t have a lot of friends. I don’t do a lot of things. I’m with my family, I write, and I read.”

And Backman prefers that, really. But in 2017, another strange thing happened: the movie adaptation of A Man Called Ove was nominated for an Academy Award for best foreign film. (Tom Hanks is starring in an English-language adaptation scheduled to be released in 2021.) Backman and his wife, who handles the business aspects of his career, flew to L.A. for the Oscars, but they’d only gotten one ticket, and Backman wasn’t keen to go to the event by himself. “There was no way I’d be there without my wife,” he says. “So she went with the film crew, which they were very happy about; they were like, ‘We get the fun one!’ ”

Backman, instead, went on a guided tour of Dodger Stadium, “which was great—me and a bunch of old men who didn’t even know the Oscars were going on.”

Maybe, at some point, everything will calm down. “It was never my intention to have this career,” he says. “I haven’t been comfortable with it at all. We’ve slowed it down on purpose. Most of the weird things now, I think, will happen in my kids’ lives, and I’ll just tag along. I’m looking forward to that way more.”

Jen Doll is the author of the YA novel 'Unclaimed Baggage' (FSG) and the memoir 'Save the Date: The Occasional Mortifications of a Serial Wedding Guest' (Riverhead).

Correction: An earlier version of this story said the English language film adaptation of A Man Called Ove was set for this year. The film is slated for 2021.