A new film that opened on July 8 focuses attention on a long-ignored war crime — the sanctioned and systematic rape of Polish nuns during World War II.

The Innocents” (“Les Innocentes”) tells the story of a young French doctor who is called to a Polish convent to aid a young novice in a breech labor. She discovers that Soviet soldiers, with the approval of their officers, raped dozens of the nuns during the occupation, leaving five of them pregnant.

But at the core of the film is the most perplexing question raised by war — why does God allow bad things to happen to good people? The faithful nuns wrestle with severe doubt, while the atheist doctor respects their faith.

The “film manages to respect faith, even though it refuses to partake of it,” Justin Chang writes in his Variety review. “And its dramatic progress is often defined by the push-pull of its characters’ opposing world views.”

The film, a joint project of Polish, French and Belgian filmmakers, had its U.S. premiere at the Sundance Film Festival in January with the title “Agnus Dei.” It opened with its new title around the country to generally favorable reviews.

The story is based on real events.

In 1945, 27-year-old Madeleine Pauliac, a doctor, was working with the Red Cross in Poland when she was called to the bedside of a nun in labor. According to her notes, the nun was from a convent where advancing Soviet soldiers raped 25 religious sisters, killed 20 more and left five pregnant.

Pauliac, renamed Mathilde Beaulieu in the film and played by French actress Lou De Laage, was killed a year later in an accident while still working with the Red Cross.

As gruesome as the nuns’ experience was, it was common. Polish scholars — who were unable to study Soviet atrocities until the collapse of communism in their country in 1989 — estimate that as many as 100,000 Polish women were raped by Soviet soldiers.

Katherine R. Jolluck, a professor of history at Stanford University, is one of only a handful of U.S. scholars who have studied the plight of Polish women in the World War II years. She has said their stories have remained hidden due to a sense of shame and dishonor.

“Those women who succumbed, out of grim necessity or force to the Russian ‘hell,’ became dirty, their bodies and social identities stigmatized,” she writes in  “Gender and War in Twentieth-Century Eastern Europe.”

That assessment is reflected in the film. The mother abbess, played by Polish actress Agata Kulesza, fights to keep the nuns’ rapes and pregnancies secret for fear it will mean the closure of the convent.

Director Anne Fontaine immersed herself in history and convent life before shooting the film in January 2015. She spent weeks in a Benedictine convent — the same order depicted in the film — and imitated the life of a novice.

“What touched me the most, and what I attempted to convey in the film, is how fragile faith is,” she said in a pre-Sundance interview.

“We often believe that faith cements those who are driven by it,” she added. “That’s an error: as (Sister) Maria confides to (the doctor) Mathilde in the film, it is, much to the contrary, ‘twenty-four hours of doubt for one minute of hope.’”