Where mysticism's often meted out in meticulously slow fashion

An apocalyptic tale set in the Dust Bowl that blends elements of “Twin Peaks,” “The Exorcist” and “The Grapes of Wrath” doesn’t seem a good fit for a pay cabler with an acumen for urban-based dramas such as “Sex and the City” and “The Sopranos.”

But with gritty period drama “Deadwood” also staking its claim on HBO these days, “Carnivale’s” inclusion on the signature Sunday night sked doesn’t seem so, well, freakish.

The series — tracking merging storylines of a fugitive carnival worker and a priest who will meet, supposedly, somewhere down the line in an epic battle of good vs. evil — wound up with 3.5 million viewers for its finale. It drew 5.3 million for its premiere.

A Depression-era scholar who had often wondered why the Wild West has been far more mythologized in movies and books than the 1930s, exec producer and creator Daniel Knauf actually completed a “feature”-length screenplay for what would eventually turn into “Carnivale” in 1991.

“It was like my third or fourth script, so I was too inexperienced to know that this was not a feature,” Knauf explains. “When I got to page 80, and I still wasn’t in my second act, I began to get a hint.”

The script — a “big story about God vs. Satan set in the Depression,” as Knauf describes it — sat in his desk bottom drawer, while he worked sporadically in Hollywood, fleshing out his family’s income with an insurance career.

Save for a 1994 movie he wrote for HBO, “Blind Justice,” Knauf admits he didn’t know anyone in TV. And he was becoming quite discouraged with the state of the feature business by 2001, when he decided to give his writing career one last push — and his “Carnivale” script fell into the hands of TV producer Scott Winant. That led to a meeting with producer Howard Klein, and further down the road, with HBO brass.

“It was a tall order (for HBO),” Knauf concedes. “It wasn’t like I had come to them with an Oscar tucked under my arm like (‘Six Feet Under’ creator) Alan Ball. And the only thing they had on the air at the time were urban dramas. We just happened to hit them at a time when they were thinking of taking a very different direction in their original series.”

Best episode: “Babylon.” The Carnivale stumbles upon an eerie Texas mining town and loses young Dora Mae to a village of damned men.

Most complex character and why: Brother Justin Crowe. A life of spiritual service masks the true demonic nature of the man from even himself, but his powers of manipulation, and his fire-and-brimstone sermons, slowly reveal the truth.

What should happen next season: “I think what we’ll see is more intrusions of Carnivale into Brother Justin’s world, and more intrusions of Brother Justin into Carnivale,” says Knauf.

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