Loving's Joel Edgerton and Ruth Negga talk about their acclaimed new film at Cannes
Credit: Andreas Rentz/Getty

Richard and Mildred Loving became icons of the civil rights movement when their fight to marry led the Supreme Court to rule all bans on interracial marriage unconstitutional.

But beyond the couple’s part in the historic ruling, Ruth Negga – who plays Mildred in the film adaptation of the story, Loving – tells PEOPLE and Entertainment Weekly that she was drawn to the part because of the couple’s enduring love for one another.

“I’d seen the documentary, and I was so struck by this couple,” the Irish-Ethiopian actress explained at the Cannes Film Festival, where Loving swiftly began generating Oscar buzz. “Individually, but also their love for each other just seemed such a beautiful, delicate, rare thing. I felt such outrage on their behalf, like many others, that the simple act of wanting to be married to another human being would incur the wrath of the law and also make people really angry. So angry – violently angry. I was just so shocked by that.”

Australian actor Joel Edgerton stars alongside Negga as Richard Loving. “Dramatically, I was drawn to this struggle, this very silent struggle of two people who were just so put upon that they didn’t really have a voice or the actions to navigate or overcome this situation,” he said. “So there was this sort of very gentle but monumental civil rights shift in America that not enough people know about.”

To prepare for the role, Edgerton explained, “We went to the cemetery where Richard and Mildred were buried. We went to the prison where they spent the first incarceration, and [we] started to get a sense of the story we were telling in a more deep way.”

And while Edgerton acknowledges there is “dignity” in the couple’s stoicism, he believes “the greatest tragedy in this story is the couple’s inability to have any avenues at first to escape this situation, and so they were robbed of time.” He added, “Yes, they got to stay together, and yes they had three beautiful children – but they were told where to live and they were robbed of the freedom of time they had to spend with their extended family, and that I felt very sad about.”