“Promised Land” is a contemporary drama from Participant Media — the company that brought us such activist movies as “Fast Food Nation” and “North Country” — about a community in the throes of the natural gas boom. But viewers expecting a morality tale about the big bad gas man and the little people he tries to frack might be in for something of a surprise.

This wispy, over-earnest movie stars Matt Damon as Steve Butler, a good corporate road warrior for a $9 billion energy company whose speciality is convincing poor farmers to lease their lucrative land for a relative pittance. He’s so good at closing — and bringing deals in “under the price point” — that he’s up for a big promotion, an opportunity made clear to him when at a lunch meeting over the second bottle of Chateau Margaux.

Hours later, he’s taking the bus into the small dairy farming town of McKinley, Pa., where he rents a beat-up car with his co-worker Sue (Frances McDormand). After buying some flannel shirts and work gloves, to better fit in with the locals, they begin to make their time-perfected pitches, Steve ingratiating himself with kids (“Are you the owner of this place? You’re not?!”), Sue talking about expanded tax bases for better schools, and both of them answering the same inevitable question about how much the land is worth.

There are a few naysayers, chiefly a local schoolteacher played by Hal Holbrook who asks inconvenient questions about soil contamination and tap water bursting into flames. Soon, Steve and Sue are faced with an interloping environmentalist in the person of Dustin Noble (John Krasinski), whose name pretty much says it all.

Written by Damon and Krasinski from a story by Dave Eggers, “Promised Land” isn’t a particularly arresting piece of filmmaking (it’s directed by Gus Van Sant in what looks like a well-meaning, left-handed project). But it benefits from one refreshing twist in a corporate villain who isn’t really a villain, a man motivated not by avarice and greed, but by compassion. Steve is from a small Iowa town that was decimated when the Caterpillar plant went out of business. Dismissing the family-farm ideal as “delusional self-mythology,” he explains, “I’m not selling them natural gas; I’m selling them a way back.”

The twist, when it comes, is a surprise but not a shock. What’s more, despite their Everyman appeal, Damon and Krasinski don’t create much by way of emotional investment, instead becoming mirror images of their most mild-mannered, white-bread selves.

“Promised Land” is helped mightily by McDormand, who, as always, injects a jolt of welcome dry humor into every scene she’s in, and Rosemarie DeWitt, as a local girl both men try to date. When these formidable actresses are on screen, “Promised Land” fizzes and pops; otherwise it’s an attractive, well-intentioned dry well.

R. Contains strong language. 106 minutes.