While illustrating the situation in Ghana, “Big Men” exposes how oil riches haven’t trickled down in Nigeria, leading to groups of bandits sabotaging oil production and selling oil on the black market. (Tribeca Film Festival)

Documentarian Rachel Boynton must have some serious powers of persuasion. Not only did she get remarkable access to the employees and boardrooms of an oil company on the cusp of a massive discovery, but she also interviewed masked, armed bandits in Nigeria, corrupt government officials in Africa and dealmakers at the Blackstone Group investment firm.

But Boynton’s most impressive feat in “Big Men” is how she takes an impossibly convoluted scenario, makes sense of it and tells a story that’s riveting on its own but also serves as a parable about greed and human nature.

If “Big Men” were a fictional movie, it would be something akin to “Syriana,” with characters from all corners of society demonstrating how a big oil discovery affects their lives. The most prominent player is Jim Musselman, the founding partner and chief executive of fledgling Kosmos Energy. His company, with the help of Blackstone and other investors, has taken a huge risk betting on oil fields off the coast of Ghana when the movie opens in 2007. With big risks come the potential for big rewards: As the pioneering exploratory company, Kosmos secured a sweet deal from Ghana’s government (and its state-run oil company) should the Jubilee oil field pan out.

Jubilee turns out to be a trove of black gold, which is good news and bad news for Kosmos. Once a new president takes over in Ghana, the favorable deal the company struck with the previous administration isn’t quite so iron-clad as it seemed. It’s Ghana’s oil, President John Atta Mills reasons, and the people of Ghana should be the ones to prosper from the discovery. Meanwhile, the U.S. Department of Justice starts asking Kosmos some pointed questions about bribery, which Musselman, an affable Texan, greets incredulously. Welcome to the big leagues.

To give some additional context to what’s at stake, Boynton travels to Nigeria, another African country blessed and cursed with oil resources. The discovery, initially made in the 1950s, has been a boon for corrupt politicians, who have embezzled hundreds of millions of dollars. But much of the rest of the country has remained in stark poverty. Groups of desperados have responded to the injustice by either sabotaging oil production or draining pipelines and selling the oil on a thriving black market.

Wrangling so many stories and all of the necessary information into one documentary is an incredible feat, and editor Seth Bomse pieces it together in a way that’s both informative and surprisingly suspenseful as the discord between Musselman, his investors and government officials in Ghana grows. To her credit, Boynton doesn’t seem to have an agenda here so much as a desire to explain what’s happening and letting each participant tell his or her story. What she makes clear, though, is that the possibility of disaster is very real for everyone involved.

“Big Men” harkens back to such mythology as King Midas and Pandora’s Box. But unlike in those fated tales, Boynton has the foresight to see the potential tragedies before they become a reality.

★ ★ ★ ½

Unrated. At Landmark’s E Street Cinema. Contains nothing objectionable. 99 minutes.