For a director, every film is special. But for filmmaker Bryan Singer, making “Valkyrie” was different. To film this story, about a plot to assassinate Hitler during the waning days of the war, he spent months in Berlin — and experienced sentiments he still finds difficult to verbalize.

“My cinematographer, Newton Thomas Sigel, and I were the only Jews,” Singer said in a recent telephone interview. “Being Jews in that environment, living in Berlin, making this type of movie, did have a different effect on me than it did on the rest of the cast and crew. But I couldn’t tell you what it is. Knowing a little bit of Holocaust history, it can be a little … “

He pauses, searching for the right word. “It’s just different,” he says finally. “Berlin is a city seeped in history. The ghosts of the second World War are everywhere.”

“Valkyrie,” which stars Tom Cruise and opens Thursday, Dec. 25, is a combination of an action thriller like “Mission: Impossible” and a PBS documentary. It’s also a film that has landed Singer, who came to prominence with “The Usual Suspects” in 1994, in something of a pressure cooker, as there are reports that the fate of the United Artists studio hinges on its success.

“I don’t think about that,” Singer says with a laugh.

Maybe not, but the pressure has affected the perception of the film. Cruise heads United Artists, which has gone through an executive reshuffling and badly needs a hit. Cruise, familiar with the “Valkyrie” project as a UA executive, signed on to play Col. Claus von Stauffenberg.

But problems began early on, when the German Defense Ministry threatened to refuse Singer access to sites if Cruise, a Scientologist, was cast in the film. The German government considers Scient-ology to be a cult-like business, and keeps the church under domestic surveillance.

Singer maintains that once he explained the seriousness of the film, the government relented. Still, the kick-’em-when-they’re-down experts went into a feeding frenzy. They didn’t like the early posters of Cruise in an eye patch. They didn’t like that he didn’t speak with a German accent (at Singer’s direction). One online writer even criticized the way he gave the Nazi salute.

Others, however, are saying that Cruise turns in a credible performance as von Stauffenberg, who was a leader in the 1944 plot to kill Hitler. For many viewers, it will be a revelation that this plot was more than just a briefcase bomb, but rather plans for a widespread coup to take over the reins of power. Stauffenberg’s diary pointed to what he felt was a duty to “no longer to save my country, but to save human lives” and also expressed his “disgust” at “the murder of civilians, the torture and starvation of prisoners, the mass execution of Jews.”

“The events here were extraordinary,” Singer says. “I didn’t want to make a languid biopic.”

This is not the first time Nazis have appeared in one of Singer’s films. They showed up in his X-Men films (the main villain is a Holocaust survivor, and Nazi soldiers are featured in flashbacks) and in his adaptation of the dark Stephen King novella “Apt Pupil,” about a boy who discovers his neighbor is a fugitive Nazi war criminal.

Singer was adopted shortly after birth by a Jewish family in New Jersey. The family was mostly secular, but talked often of family members lost in the Holocaust.

When he was a child, Singer used to play war with his friends. “Sometimes I’d be the American soldier and sometimes I’d be the German,” he recalled. “When my mother found out about that, she gave me a pretty stern lecture about what 6 million meant and how it extended to our family.”

It’s a lesson he’s never forgotten.

“Valkyrie” opens in Bay Area theaters Thursday, Dec. 25.