The Promise takes on the still-incendiary subject of the 1915 Armenian genocide in the context of a sprawling wartime love story, with mixed results.

The treatment of ethnic Armenians in the waning days of the Ottoman Empire gets a thorough journalistic/historic airing, but the star-crossed romance at the movie's heart is consistently flat. This despite the attractive cast, headed by Oscar Isaac as Armenian medical student Michael, who leaves his village (and new bride) to study medicine in Constantinople. Just before the outbreak of WWI, it is a cosmopolitan capital where people of many faiths and races join the hustle and bustle of a thriving international city (period detail is good, if obviously digital in many cases).

Michael falls hard for Ana (Charlotte Le Bon),  the governess who works in the house of the wealthy Armenian where he is staying. The attraction is mutual, though she is involved with a crusading journalist, Chris (Christian Bale), a hard-drinking, quick-to-anger, but widely traveled and highly astute fellow who understands that the nation, and Europe, are atop a powder keg of ethnic, political, and nationalist tensions – the Ottoman Empire is ending, a new Turkey is being born on the eve of world war, and it will be a bloody delivery.

He urges Michael and Ana to leave, but they stay out of love for their people and each other. They consummate their feelings on a night of anti-Armenian riots in Constantinople, the kind of big, dramatic gesture that tends to fall flat in The Promise.

Michael and Ana are soon engulfed by the anti-Armenian hatred that grips the country – shops destroyed, property seized, Armenians expelled or herded into prison camps. Michael is pressed into slave labor, Ana finds her way to refugee camps, Chris travels the country in a dangerous bid to document and expose atrocities, a thread that becomes director Terry George's unblinking eye on the dreadful scope of the genocide.

George (Hotel Rwanda) wants to give the movie an epic sweep, and The Promise has the appropriate cast-of-thousands scale – it was funded by the late Kirk Kerkorian, a U.S. billionaire investor of Armenian descent (he called his production company Survivor Pictures, and labored for years to get the movie off the ground. He died in 2015, after seeing the production begin).

Still, the passions driving the filmmakers are mysteriously absent on screen. Important relationships feel inert. The characters cheat death, endure imprisonment, climb mountains, ford rivers, fight ferociously – they diverge and converge, reuniting in weepy embraces set to swelling music, gripped by emotions that, unfortunately, we do not share.

You can see what the movie is after here – Dr. Zhivago is an obvious model – but George lacks David Lean's command of the epic form, and his movie, while important, strains to match his ambitions.