A little over three years ago, Patrick deWitt sold his car, flew to Paris and moved into a former convent.

It didn't necessarily change his lifestyle much. The Portland novelist was already living a hermetic life here, and besides, he could steal Wi-Fi from the iPhone of his neighbor in the cloister. But it did change what he wrote. In the nunnery, deWitt says, he lost a novel.

For more than a year, he had been writing a book about a Bernie Madoff-style investor. It was meant as a follow-up to his blackly comic Western The Sisters Brothers, which in 2011 had shortlisted the Canadian native for the greatest literary prize in the British Commonwealth, the Man Booker.

The monastery, now an arts colony subsidized by the French government, was deWitt's final hope of saving his next book. "I was attempting to plumb the depths of the psyche of a man obsessed with money," he says. "I thought this would be interesting. It was super-boring."

He's speaking from the sparsely decorated home he recently bought in Portland's Overlook neighborhood.

The slender, almost gaunt author—monastic-looking himself apart from a few faint tattoos, including the words "thank you" on the palm of one hand—has spent the past five minutes brewing me a strong cup with his Italian-style stovetop coffeemaker, but has for his own part abstained.

He speaks softly and with articulate bemusement, a serene presence until he unfolds his arms to gesture with his hands, at which point he often fidgets or lightly scratches—an arm, his chin, back to the arm—before returning to rest.

DeWitt's forthcoming third novel, Undermajordomo Minor, out Sept. 15, is the book he found instead, while reading old European fables to his first-grade son in the halls of a monastery he says felt haunted enough he dreaded the five steps to the laundry room's light switch. It's a "fable without a moral," he says, set in a lonely European castle from long ago, surrounded by a war that is never explained.

Each of his books, deWitt says, carries a thin thread of autobiography. His first novel, 2009's Ablutions, was a tortured drunk- and drugfest based in part on him. In The Sisters Brothers, deWitt says he sees himself in Eli Sisters' feelings of isolation, while in Undermajordomo Minor it's antihero Lucien Minor's love of lies as an art form.

Which is to say: alcohol abuse, loneliness and lies.

"Those are the three tenets of my life," he says, smiling. "The guiding lights."

DeWitt had been trying to avoid novels set in the past, in part to avoid hamstringing art with the strictures of fact. This comes despite his success with the historical form. The Gold Rush-era Sisters Brothers is a singular work—bloody and in full humor, driven by a tattered formality of speech and the peculiar morals of murderous Eli and Charlie Sisters. And for at least a week in 2011, it was the top-selling book in deWitt's native Canada. Bookmakers in England were placing odds on whether his novel would win the Man Booker Prize. ("My odds were shit," he says.)

But historical books still require fealty to the past, which is a problem. "That's never an appealing thing, to have things that are required," deWitt says.

Much of his research for The Sisters Brothers involved "mutilating" an old book called The Forty-Niners he'd picked up at a yard sale, pasting up pictures of cowboys and prospectors and then writing vividly realized characters to fit the images. Even though he ended his book at a bar in Oregon City, he has never been to a bar in Oregon City.

"Oregon City is 10 minutes away," deWitt says. "I knew it was there."

Undermajordomo Minor avoids specificity of setting altogether. Like The Sisters Brothers before it, deWitt's new book is a thing of tumbledown beauty, a deadpan picaresque that turns its genre inside out. It takes place both nowhere and everywhere, a murky vision of old Europe inspired in part by the postwar fables of Italo Calvino and Czech novelist Bohumil Hrabal, but especially a book about a misanthropic dwarf by Swedish novelist Pär Lagerkvist. Part of the great success of the book is its rootlessness—the feeling that anything is possible. A noble might eat a rat, while a man might lose three fingers to mild pique.

Lucien "Lucy" Minor, the "undermajordomo" of the book's title, is an amoral weakling from a village of dimwitted giants who flees to work at a castle mostly because he feels the townspeople don't like him enough. He is boastful and untalented, with no greater aspirations than "not to die" and to avoid boredom. Upon leaving town, he cheerily rejects being his mother's son, and out of lighthearted spite he tells a town girl her future husband is unfaithful.

"I had him in mind as classic fable or fairy-tale protagonist," deWitt says. "In fairy tales, oftentimes he's a weakly hero, oftentimes a flawed individual. Lying and liars are common themes. Fables typically are cautionary tales, something with a moral attached. I knew I didn't want to teach anybody anything, and I'd never assume a moral high ground."

DeWitt has abandoned carousing, he says, for a settled existence punctuated by travel—and is surprised how deeply he's become attached to his new home despite not really knowing how to fill its space. A room by the kitchen sits unfilled, a bare bulb swinging over a bare floor.

"Once I was a pig; now I'm not," he wrote in an email a few days after our interview. "I might take a hint of whiskey here and there to be sociable, but otherwise I'm an old lady darning socks by the fire whistling a moldy tune through the gap in my teeth and wondering who's going to carry me up the stairs, to bed."

He has removed all Internet, in further abstention. "I was a year late on this last book," he says. "At a certain point, I felt I wasn't going to make it." And so he removed all Web access from his home and phone, which allowed him to finish without toxic distraction.

But even after turning in Undermajordomo Minor, deWitt says he'll keep the Internet from his home "until somebody comes to the door, like a policeman demanding that I get it." His current flip phone causes people to pity him in public.

"I tend to hole up when I work, and it forces me to go out every day," he says. "This is obnoxious, but oftentimes when I go to the coffee shop, I will have a list of things that I need to do with relation to the Internet, like look up someone's phone number."

But then, drunkenness and self-abnegation are often mirror images—just different ways of letting go. In deWitt's books, the grim and joyfully funny often combine in the same image, as when in Undermajordomo Minor the undertakers slip and notch a miraculously bloodless divot into the head of a man who died with a sneer.

DeWitt has had to get used to letting go of his novels. In addition to the Madoff book, he also had to scrap a novel between Ablutions and The Sisters Brothers. Upon mentioning his next book—a story about an explorer in a bygone era—he worries he's already jinxed it. But maybe, he says, some things deserve to go lost.

“A lot of authors, judging by their list, will put anything out that they finish,” deWitt says. “I was watching Woody Allen recently, and you know he’s this guy that puts out a movie every year. That’s the worst model I’ve heard of in my life. It’s just idiotic. Why wouldn’t you just wait for the good ones?” 

GO: Patrick deWitt is at Powell's City of Books, 1005 W Burnside St., on Tuesday, Sept. 15. 7:30 pm. Free.