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While much of the country is plagued by high unemployment, Williston, N.D. has been bolstered by an oil boom. With fracking a big and profitable business, the small town’s population has almost tripled over the past decade, as the state's unemployment rate has shrunk close to nil.

The lure of high paying jobs in the oil fracking industry has attracted men from all over the country, more than Williston can hold. So local pastor Jay Reinke opened the doors of his Concordia Lutheran Church to allow these "overnighters” to stay on either short-term or long-term basis.

That’s where the though-provoking documentary “The Overnighters,” being shown at the Sundance Film Festival, begins.

“I didn’t want to make a movie just on the oil boom. Here were dozens of men sleeping on the pews and on the floor and in their cars in the church parking lot,” director Jesse Moss told FOX411. “You go to a boom town because you need a second chance. These are men running from mistakes they have made in their lives.”

Big mistakes.

Reinke, who states early in the film that “not only are these men my neighbor, the people that don’t want them here are also my neighbors,” performed background checks on his boarders, and learned that some were registered sex offenders. That fact sparked immense controversy within the community, with many calling for Pastor Jay to stop housing the men. Support for his program further eroded when Reinke invited one sex offender, Keith, into his family home over concerns that his presence at the church would evoke condemnation from the local newspaper.

It is the moral imperative “love thy neighbor” that is routinely examined throughout the film. Did Pastor Jay do what was right? What risks is one willing to take to practice what he preaches? “The Overnighters” explores the tension this as well as the tension in the small, conservative community when confronted with the surge of frantic, job-seeking strangers.

“It’s not just a religious issue, it is a moral issue,” said Moss, who slept on the church floor with the overnighters for six months, enduring repeated attacks and threats. “It was a raw, emotional place. Desperation forces people to drop their usual defenses. Men cried as they showed me pictures of their children. They told me about their dreams of lucrative jobs on the oil rigs that checkered the prairie landscape.”

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