“The Promise,” a sweeping historical romance starring Oscar Isaac and Christian Bale, is the kind of movie epic they just don’t make anymore. It’s a throwback to David Lean’s “Doctor Zhivago” and Warren Beatty’s “Reds,” movies that transposed big, emotional stories against a sprawling canvas, and tugged at the heartstrings while dealing with thorny political periods.

It’s risky, but not just in that way. Not only is it one of the most expensive independently financed films ever made, it also deals frankly with the Armenian genocide. The mass killings of 1.5 million Armenians by the Ottoman Empire took place between 1915 and 1922, but decades later, the episode remains politically fraught. Bringing the story to the masses was a mission for Kirk Kerkorian, a businessman of Armenian descent who once owned Metro-Goldwyn-Mayer. He died in 2015 as the film was going into production.

“This was personal for him,” says Eric Esrailian, one of the film’s producers. “He always wanted to make an epic film with the best actors available that wouldn’t just be a history lesson.”

His vision wasn’t cheap. “The Promise,” co-written and directed by Terry George (“Hotel Rwanda”), cost nearly $100 million to make before tax breaks. Kerkorian provided all of the financing through Survival Pictures, a company he set up with Esrailian. The film, which premiered at the Toronto Film Festival, has yet to close a distribution deal. Esrailian thinks the subject matter may be scaring some buyers away.

There’s a reason for that fear. Officials in Turkey continue to deny that systematic killings of Armenians took place. “I’ll just say that there are some studios that have business interests in Turkey, and you can form your own opinion,” says Esrailian.

“I’ll just say that there are some studios that have business interests in Turkey, and you can form your own opinion.” Eric Esrailian

There were no public protests at the Toronto premiere, but there is already evidence of a propaganda campaign to discredit “The Promise.” The film’s IMDb page has received more than 86,000 user votes, the bulk of them one-star ratings, despite the fact that the movie has had only three public screenings. That’s more user reviews than appear for “Finding Dory,” the highest-grossing film of the year. The filmmakers say reaction on social platforms has been equally intense.

“The day after we screened the movie, 70,000 people went on IMDb and said they didn’t like the movie,” says Mike Medavoy, one of the film’s producers. “There’s no way that many people saw the movie after one screening. There aren’t that many seats in the theater. ”

“The Promise” centers on a love triangle involving a medical student (Isaac), a journalist (Bale), and the Armenian woman (Charlotte Le Bon) who steals their hearts. All three find themselves grappling with the Ottomans’ decision to begin rounding up and persecuting Armenians.

“Some critics blamed us for being old- fashioned,” says George. “But that’s what we set out to do. We wanted as wide an audience as possible.”

This isn’t the first attempt at a movie about the Armenian genocide. In the 1930s, MGM planned to adapt “The Forty Days of Musa Dagh,” Franz Werfel’s novel about the massacres and deportations of Armenians, starring Clark Gable. That production was abandoned after the Turkish government threatened to launch a worldwide campaign against it.

Studios may have a reason to be cautious. The film business is an increasingly globalized one, with major movies depending on foreign revenue to make a profit. When Hollywood has dramatized the genocide, the blowback has been fierce. Atom Egoyan has the scars to prove it: His 2002 film “Ararat,” which depicted a Hollywood director trying to make a film about the genocide, was the focus of a vast campaign targeting the film’s distributor, Miramax, and Disney, its parent at the time. The studio received so many negative emails that its website crashed.

Egoyan warns that the controversy is just starting. “It’s going to be a tough ride,” he says. “The denialist lobby is very well-organized.”