New York ? In any other context, it’s a mundane act. Yet when a real estate agent walks through a vacant house to end the PBS documentary “Flag Wars,” it seems sinister.

The film about blacks and gays fighting about the future of a neighborhood in Columbus, Ohio, opens the 16th season of the PBS series “P.O.V.” at 9 p.m. Tuesday.

The title refers to the flags filmmaker Linda Goode Bryant spotted when visiting her father in the working-class black neighborhood known as Olde Towne East in Columbus. She naively thought it had something to do with a flower show.

Instead, the rainbow colors fluttering outside homes owned by gay men and African flags on other houses symbolized a conflict tearing the community apart.

Gay men seeking an urban enclave were buying and renovating Victorian homes in Olde Towne East. They felt they were improving a neighborhood down on its luck but instead antagonized black families who had been there for years.

Bryant felt it was an interesting story and spent four years filming it with Laura Poitras.

“I personally entered with the assumption that because both groups had a shared history of oppression in this society, that that would create an immediate kind of bond between them,” said Bryant, who’s black.

The fact that it didn’t “was really disheartening to me,” she said.

Poitras, a white lesbian who recently moved into a Harlem home with a partner, brought a different perspective.

A rainbow flag hangs outside a restored house in Olde Towne, Columbus, Ohio. The new documentary Flag

“My expectation wasn’t that it would create common ground,” she said. “My expectation was that the status of the gay community and the status of being marginalized would create blinders to the residents who lived there.”

The gays moving in are clearly wealthier than longtime residents. But they’re still minorities not fully embraced by society; Bryant emphasizes that point by including a scene where a right-wing minister rails against legislation designed to protect gays from attack.

“I’ve heard it countless times — victims are the worst victimizers,” she said. “I don’t understand that about human behavior. I’m hoping at some point that’s a conversation that is engaged as a result of this film.”

Their film is the first of five productions planned by “P.O.V.” this year that are financed by public broadcasting’s Diverse Voices Projects. Black, Latino, Asian, American Indian and Hawaiian filmmakers received money for projects

Although “Flag Wars” takes place in Columbus, the filmmakers say similar gentrification is taking place in Boston, Atlanta and Chicago.