Sam Savage, 69, has a past far removed from his bungalow in the funkiest neighborhood in Madison, Wis., where he channels the voices of angst-ridden creatures leading lives of quiet desperation. His second novel, The Cry of the Sloth: The Mostly Tragic Story of Andrew Whittaker, Being His Collected, Final, and Absolutely Complete Writings, will be published by Coffee House Press this September, following his successful debut, Firmin: Adventures of a Metropolitan Lowlife (Coffee House, 2006).

Savage has always considered himself a writer. But it's taken him almost a lifetime to find his voice. “I know how to begin things,” he says of repeated attempts over the years at writing fiction. “And not completing; I know all about that, too. I did a lot of first chapters, and more than that, first paragraphs. I did a lot of writing.”

But writing Firmin was different. “I heard a voice,” Savage recalls of his first novel, written in six months, “and I just knew. From that point on, I could write, as long as I could hear this voice.” The tale of a rat silently eking out a hardscrabble existence while literally devouring books in a doomed Boston bookstore resonated with critics and readers alike.

“I was astonished,” Savage says. “I thought [sales] would be in the hundreds. It sold a fair amount in the United States, but it did 10 times in Europe what it did in the United States.” Coffee House Press sold 11,000 copies before selling all available world rights to Spanish publisher Seix Barral in 2007. Firmin has been published in more than 20 countries and translated into as many languages. The Italian edition topped bestseller lists last year, selling more than 300,000 copies.

With The Cry of the Sloth, Savage once again literally heard a voice—this time, that of Andrew Whittaker, a middle-aged literary journal editor and aspiring novelist, whose writings and correspondence over the course of four months reveal a man whose life of solitude seems to be driving him mad. Or maybe not.

A soft-spoken native Southerner, Savage describes an idyllic youth in rural South Carolina, interrupted at age 17 when his father, the mayor of a small town and a published author, “stood up against the Klan” and fled to New England with his wife and three children after a cross was burned in the family's front yard.

Savage dropped out of high school, but got into Yale in 1960 by acing his SATs, then left three months later. After “wandering” between Chapel Hill and New York for a year, he took part in a three-month-long civil rights march from Nashville to Washington, D.C., and got arrested on the steps of the Pentagon. He moved to France, lived hand-to-mouth for several years and returned in 1968 to complete his college studies, later earning a Ph.D. from Yale in German philosophy in 1979.

“I never used it. I taught at Yale for a year and a half as an acting instructor, but I went back to France for four years, where I did nothing. I drank. I drifted around in Paris,” he admits. “Philosophy was a mistake, a detour.”

He did meet his third wife, Nora, there, and they came back to the U.S., to Cambridge, Mass., where Savage “fixed bicycles and did carpentry” before settling down in a small town near Charleston, S.C., building a house and raising a family. Four years ago, they moved to Madison, to better accommodate a disabled daughter who could more easily live independently in a city.

Asked if he hopes to build upon Firmin's success with a novel that touches upon similar themes of solitude, alienation and the power of imagination, Savage laughs, and says, “I'm 69 years old. I'm not out for a literary career.” What really matters, Savage says, is that not only did Firmin touch readers in “an important and existential way” but it did him as well.

“I learned an incredible thing: I could complete a novel,” he says, clearly still marveling at his accomplishment.

“I was mute for all those years,” he adds. “Now, there is great happiness when I sit down and write. I know I'm talking to somebody and they can hear me.”