Mark Boal, Kathryn Bigelow and Chris Pratt at the Newseum for the “Zero Dark Thirty” premiere. (Kris Connor/Getty Images)

It should have been a triumphant evening for screenwriter Mark Boal, bringing his “Zero Dark Thirty” to a debut screening in Washington, just at the moment it’s the most talked-about movie in the nation, almost certain to clean up when Oscar nominations are announced Thursday. (Update: It received five nominations.) But the epic take on the search for Osama bin Laden, while praised by critics, has been battered by Beltway types over its portrayal of torture of detainees — and the journalist-turned-screenwriter appeared, well, subdued by the onslaught Tuesday night.

“I remember hearing that the head of the CIA had made a statement about the movie,” Boal told the audience in a flat, weary tone. “It was a pretty intense moment.”

Not the typical vibe for a glittering Washington cocktail reception/premiere. Outside the Newseum, the movie had drawn a cluster of protesters to Pennsylvania Avenue (guys in orange jumpsuits and black hoods decrying treatment of Guantanamo prisoners; conspiracy types leafleting the crowd with alternate theories about bin Laden’s death). Inside, the usual array of media elite eager to get an early look at a buzzy flick, but relatively few political heavyweights joining them. The film’s director Kathryn Bigelow walked the red carpet and introduced the film — but ducked out before the Q&A to pick up an award from the National Board of Review in New York late that night.

Jessica Chastain in “Zero Dark Thirty.” (Jonathan Olley)

Bigelow and Boal (who won Oscars for 2009’s “The Hurt Locker”) have touted the first-hand reporting that went into the movie, including interviews with administration officials and operatives involved in the 2011 Abbottabad raid. But how accurate is the final product? Three senators sent a blistering letter calling a scene “grossly inaccurate and misleading” for implying that waterboarding a detainee led to a major break in the search for bin Laden; CIA Acting Director Mike Morell followed up with a more finely shaded critique, arguing that the movie inaccurately made it seem like torture was “the key” to finding the terrorist, when in fact only “some [intel] came from detainees subjected to enhanced techniques.”

Moderator Martha Raddatz prodded Boal gently: Truth? Or fiction?

“The research is over here in a pile,” said Boal, “and then I had to write a movie.”

He said that the movie attempts to capture what “a long decade, in many ways a dark decade” — but called it “a portrayal of the dedication that the military and intelligence communities exhibited day in and day out.” He also groaned about “people talking about the movie who haven’t seen it yet.”

MPAA Chief Chris Dodd came through with a more rousing defense: “It’s a movie!” he said. “This isn’t a documentary.” Much of the story, he said, isn’t about torture anyway, but about diligent bureaucrats analyzing data in quiet obscurity: “It celebrates the work of the people of this town.”

Chris Pratt, left, and Joel Edgerton in a scene from “Zero Dark Thirty.” (Jonathan Olley)

Whew. Good thing they let us bring our drinks into the theater. Actor Chris Pratt lightened the evening with jolts of the jolly showbiz banter you expect from these events. Pratt, who played a Navy SEAL, joked about the tough living conditions with his fellow thespians on location in Jordan.

“For six weeks we were bunking together, living together, smelling each other’s farts,” he said, adding later: “For ‘Zero Dark Thirty 2,’ we’re gonna make some demands.”

Also: ‘Zero Dark Thirty’ review by Ann Hornaday, 1/11/13

Leon Panetta on ‘Zero Dark Thirty,’ 1/15/13

Read earlier: ‘Zero Dark Thirty’ and the new reality of reported filmmaking, 12/13/12

In ‘Zero Dark Thirty,’ she’s the hero; in real life, CIA agent’s career is more complicated, 12/10/12

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