The collision between global capitalism and a resource-rich third world country is at the heart of Rachel Boynton’s documentary, which focuses on a small Dallas oil exploration firm’s relationship with the government of the Republic of Ghana in West Africa. It’s not a new subject, of course, but what sets “Big Men” apart and makes it engrossing is the extraordinary degree of access Boynton had to the major parties and the deftness with which she uses it.

The centerpiece of the film is the discovery of Jubilee Field, a potentially rich source of crude found off Ghana’s coast, and the involvement of Kosmos Energy, a small startup company, in exploring it. The two men most directly involved are George Owusu, the local businessman whose group—called EO—secured exploration rights from the national oil company and contacted Kosmos about providing backing for the venture, and the firm’s CEO and point man Jim Musselman, who, in partnership with Owusu, began developing a working relationship with both the government and local tribal leaders. Meanwhile Kosmos solicited financial backing for the hugely expensive work of pumping from the site from a big venture capital firm, the Blackstone Group.

But while taking advantage of her access to Musselman and Owusu—as well as government officials—Boynton offers a cautionary message by looking at the situation in nearby Nigeria, where massive oil reserves were found in the 1950s. That set the stage for decades of brutal exploitation in which billions in profits found their way into the bank accounts of corrupt officials and international companies while little of the profit was directed toward the improvement of the nation as a whole. She looks particularly at the current situation there, with ski-masked rebels sabotaging oil pipelines (she even manages to interview some of them) and small-timer profiteers siphoning off crude from the lines to market as an alternative to expensive gasoline (a process that can be very dangerous for all concerned).

The apparent smooth sailing of the Ghana operation, meanwhile, is endangered by two events. One is the worldwide economic collapse of 2008, which threatens to dry up the capital needed to continue exploration. The second involves Ghanaian elections that bring in a new reformist government that begins investigating whether the arrangements reached with the former regime constituted a sweetheart deal. Kosmos executives even consider selling their share of the venture altogether, a prospect itself endangered by inquiries by the U.S. government as to whether the firm had violated bribery laws.

Along the way both Musselman and Owusu will have lost their positions, with each protesting the injustice of what happened to them even as the backers they represented work to make the operation a bonanza that will bring in massive rewards. Left unresolved is the matter of which among the players might actually give a thought to the interests of the Ghanaian people—an issue that Boynton raises with them through questions that are probing and incisive but not combative. The example of Nigeria, to which she regularly returns, also hangs over everything, providing a stark reminder of what might actually happen despite the honeyed words from all sides.

Ultimately “Big Men” raises the fundamental issue of whether greed is a natural element of the human condition (as Milton Friedman suggests in an opening quotation), and whether once unleashed it can be tamed to any significant degree—especially since from a practical perspective the costs of oil exploration are gigantic, and dry wells are far more common than productive ones though no less expensive to drill, particularly offshore. As the film, expertly shot by Jonathan Furmanski and edited by Seth Bomse in a way that manages to keep things clear, shows, it’s an exceedingly complicated business; and Boynton’s documentary does an excellent job of outlining its complexity, and its potential for both great good and great damage. The result is a film that both clarifies and personalizes an important subject in a fashion that’s both skillful and compelling.