In the opening scene of The One Percent, an 80-minute expose of the wealthiest Americans, three croquet players clad all in white are filmed through the bushes of an undisclosed course. Director Jamie Johnson shot the trio on the condition that their whereabouts would not be revealed, lest the plebes discover where the leisure class put their mallets. The faces are blurred, but the sounds on the course are all audible. The brightly colored balls clink as they meet on the manicured lawn and a lady tsk-tsks as she learns the young man behind the camera has never played before.

Mr. Johnson’s inexperience with the sport is surprising. At 28, he stands to inherit a cut of his family’s $1 billion net worth. His great-grandfather was the founder of the Johnson & Johnson company. And rather than bask comfortably in the glow of his wealth, the young filmmaker is exploring the issue through documentary film.

His first, the Emmy-nominated Born Rich, follows 10 children from families like the Trumps and the Newhouses as they spend their time and their money. The One Percent, which first screened at the Tribeca Film Festival in 2006, looks at the growing wealth gap in America, focusing on the one per cent of Americans who control 40 per cent of this country’s wealth. On Wednesday evening, the film screened at the Chilmark Community Center as part of the Martha’s Vineyard Film Festival summer series and Mr. Johnson attended to speak with the audience.

“I promised them I would not reveal where they were playing,” he said of the croquet threesome following the film. “But I will say it is an exclusive, wealthy community with roots in the WASP culture. When I was coming here I wondered whether they might have relatives sitting in the audience tonight,” he continued with a smile. “There is overlap between a community like that and what’s happening on Martha’s Vineyard.”

The wealth gap on the Island first attracted film festival founder and director Thomas Bena to Mr. Johnson’s work four years ago, when he screened Born Rich to a packed house. “I chose Born Rich initially because I thought, wow, this would really fit well with our community,” Mr. Bena said in a conversation following the screening.

The film is broad in almost every aspect. It captures scenes in the Florida sugar cane plantations and inside the Beverly Wilshire Hotel in Los Angeles. It includes footage from the 1970s and news clips from Hurricane Katrina. Interview subjects range from Nobel Prize-winning economist Milton Friedman to the granddaughter of renowned American investor Warren Buffet who lives as an artist and a nanny. Because of her involvement with the film, the film reports, Mr. Buffet cut ties with his granddaughter before the documentary was even finished.

Mr. Johnson also turns the camera on his own parents. Mr. Johnson’s father, James, is curt and dismissive. He does not like the subject of the film, does not want to talk on camera and when his own words are not strong enough, he calls for backup from the family wealth advisor who helps the Johnsons spend and invest their money and holds yearly meetings with James, his wife and their six kids, including Jamie.

When James Johnson was the age Jamie is now, he was a surfer and an artist. He was also a filmmaker who helped fund and produce a documentary about apartheid and economic inequality in South Africa. After the film aired on public television, executives at Johnson & Johnson pulled the young James Johnson into their headquarters. “I learned there was another side of the story,” James Johnson said in the film.

“I think that experience of making that film changed his life,” Mr. Johnson said of his father following the screening. “It changed his political views. He used to vote Democratic and now he votes Republican. He wears a coat and tie every day, even though he doesn’t sit in an office; he sits in his house.” Mr. Johnson’s mother, who tears up in the movie behind flashy green glasses and is filmed arranging flowers in a sun room, did not come from money. “My mom had a huge impact on me. I never would have gone anywhere near the topic of making money without her influence,” Mr. Johnson said.

The film scrutinizes the American wealth gap (one segment focuses on a Chicago neighborhood where luxury condominiums have replaced housing projects, ousting hundreds of hard-working families), but following the screening, Mr. Johnson acknowledged the many ways he has benefitted from it. “I do live well. I don’t live particularly modestly. I suppose I could live more modestly,” he said in response to a question from the audience. “I spend a fair amount of money on my film projects and I participate in some foundation work and charitable giving,” he added.

Asked how his family background helped him gain access to his subjects, he said: “I would write people letters and in them, I would outline my family background. In some cases, this worked against me.” But without his personal wealth, Mr. Johnson would not have been able to finish the film, which was at first funded by HBO. After a disagreement over licensing, Mr. Johnson continued work alone, using his own money for the project. HBO later offered the highest bid on the film.

Mr. Johnson also spoke about how the current economic slowdown is affecting the extremely wealthy. “The recession doesn’t seem to be impacting this group,” he said. Many of those he interviewed were actually excited when the economy took a turn for the worse. He recalled their laments during the boom years: the overabundance of overnight millionaires, the long taxi lines at private airports like Teterborough in New York. “With the economic boom, there was more competition. The recession gives more opportunity to make investments. High-end real estate is cheaper. There are deals to be had,” he said.

In the end, Mr. Johnson expressed his hope that the film will begin to chip away at the discomfort surrounding the issue of wealth. “No one wants to justify their power and privilege,” he told the audience.