Susan Orlean asks me if she should turn down her music. “It’s a Pandora station—indie women singers,” she says.

“Please don’t,” I say, as she leads me to a plush couch in her home in rural Pine Plains, N.Y., where she spends the summer. It has floor-to-ceiling windows that show off great views of her sprawling property; plenty of cow art in honor of the real-life cows that live in the pasture outside; and a big, long table where she can spread out and do work. Ivy the dog lies at our feet for most of our conversation.

The author of bestselling reported nonfiction, including The Orchid Thief (1998) and Rin Tin Tin (2011), as well as countless dazzling New Yorker profiles, Orlean is the kind of writer who goes deep into the world of whatever topic fascinates her. I’ve taken the train to Upstate N.Y. (guided by a very detailed email from Orlean in case I got lost) to ask her about her latest work, aptly titled The Library Book (Simon Schuster, Oct.). It’s a love letter to libraries, the people who work in them, and the values they represent.

“Libraries are inherently political,” Orlean says, “in the sense that they represent some really clear democratic values of inclusiveness, and they’re the most welcoming place for immigrants.”

Orlean never meant to write one of those books that we need “now more than ever.” “When I set out to write the book,” she says, “Obama was president, and the idea that libraries represented some resistance to the political moment was unimaginable. Suddenly, I find myself with a book coming out at a moment where it feel likes it’s incredibly charged politically.”

When I ask Orlean what she thinks about a notorious, since-deleted July Forbes article in which an economics professor argued that Amazon should privatize libraries, she laughs. “The idea that libraries are in some way being threatened says everything. I’m happy to be publishing a book that’s about those values at this moment. I didn’t start out saying this is the moment to write about libraries—but weirdly, it is. Although, if I could choose for Trump not to be president and for the timing to be less beneficial for me, I would choose that.”

When Orlean began contemplating making libraries the topic of her next book, she had recently moved to L.A. with her husband, who’d been asked to help launch a startup there. She took her son to their local library branch and had what she describes as a Proustian moment: “I felt transported in time back to my own childhood. I simply hadn’t thought about it, and then I walked in and it was like, bam! It was an intense moment, and it made me that much more convinced that I wanted to write about a library.”

Then Orlean learned that the main library branch in Downtown L.A. was almost entirely destroyed by a fire in 1986 that ruined or damaged more than a million books, and she became even more intrigued. The cause of the fire remains unknown, but she delves into a few likely answers in The Library Book, including an examination of an unstable man who confessed to setting the blaze but was never convicted. “Arson is so difficult to investigate that you’re 99.9% likely to get away with it,” she says. “And the library was a perfect storm. What could have a larger fire load than a library?”

Orlean also explores the possibility that the fire was an accident. “I’m not sure it’s absolutely the thing I believe, but it was never explored at all,” she tells me.

Thus Orlean took on a reporting task that included the study of arson, of libraries in general, and of the history and modern-day goings on in the life of the main branch of the L.A. Public Library. “The scope of it struck me only as I began,” she says. “I was entering a world in which I was completely ignorant, and I’m used to that. That’s the way I tend to write books. In the beginning, the amount that you don’t know is so overwhelming that you don’t know what you don’t know. Over time you begin to realize what you don’t know. I look at writing books as though during the first half you’re a student, then you become a teacher. The moment at which you feel you’re ready to teach is the moment you’re ready to write.”

Orlean’s research led her to working from inside the library itself, shadowing many of its employees, from the head of the public information office to the head of security; sitting in on city meetings; and attending the opening of a pilot program to offer various services to homeless people. “The library is a microcosm of society,” she says. “The single biggest urban issue of our time is homelessness and its corollaries: mental illness and drug use. There is a big homeless population that comes into the library to use the computers, and now there are a lot of services for them. Libraries try hard to be open and accommodating to homeless people, while also trying to not alienate patrons who are not homeless—to do the right thing by everyone.”

The Library Book delineates these problems with nuance, even though the issues are endlessly complicated. “I’m not trying to be a Pollyanna,” Orlean says with a smile. “There are big issues that come with the library having so many homeless people, and I tried to be pretty honest about it in the book.”

Orlean understands that she is likely to take some heat for writing a book that’s so much about book lovers. “Of course there will be criticism from insiders—librarians are a feisty bunch, and I’m sure there will be a certain amount of pushback,” she says. “But I feel comfortable that it won’t be on factual stuff. It might be more about perception.”

She’s even gone so far as to hire an outside fact-checker, whom she used to work with at the New Yorker—a step that not every nonfiction author decides to take. “I said to her, ‘Be hard on me. I don’t want to be caught in a foolish mistake.’ I was proud that my manuscript held up to her scrutiny, which is harsh in a good way.”

As much as Orlean loves bookstores, she plans to promote her new book primarily in libraries. “It’s my secret hope that it will encourage people to think about and appreciate their own libraries,” she says. “Doing a tour largely in libraries would help to do that, because it would get people into their libraries. They’ve become wonderful venues.”

Orlean tells me about a particular marketing campaign by Simon Schuster that she would like to replicate: “They had a bunch of their staff members write thank you notes to librarians who meant something to them.”

“Librarians are heroes,” she continues. “They don’t do what they do to be rich or famous. They’re the front line of a lot of things that are important to us, dealing with children the way they do and opening their eyes to the excitement of reading, almost always being the first line of free speech and anticensorship. I think it would be the coolest thing in the world if this book inspired people to thank their librarians.”

Before it’s time for Orlean to drive me back to the train, along with some spiced almonds and peanuts she’s packed in a to-go baggy for me, she reflects on the current moment: “On the one hand, people seem fabulous; on the other hand, they seem horrible. I think more people generally are good—sorry to sound like I’m quoting Anne Frank now. And there’s plenty to feel joyful about: that we still write books and read books and preserve books in places like libraries where they’re available for everyone to share.”

Maris Kreizman’s writing has appeared in Esquire, GQ, the L.A. Times, the New York Times, Vanity Fair, and elsewhere.