Instead, she and screenwriter Mark Boal turned "Zero Dark Thirty" into a more complex look at the decade-long hunt for the al Qaeda leader, including a frank presentation of U.S. torture and previously undisclosed details of the mission to hunt down the man behind the September 11 attacks.

When the film opens in limited U.S. release on Wednesday, Bigelow and Boal want audiences to disregard a year of controversies, including claims, which they have denied, that the film makers were leaked classified information.

"It's about a look inside the intelligence community. The strength and power and courage and dedication and tenacity and vulnerability of these women and men," Bigelow, 61, told Reuters in a joint interview with Boal.

Bigelow won an Academy Award in 2010 for "The Hurt Locker," about U.S. army bomb disposal experts in Iraq. She says her latest movie puts the audience at the center of the quest to find bin Laden, and gives a perspective of the U.S. intelligence community and how its methods changed in the years following the September 11 attacks.

"It's a controversial topic, it's a topic that has been endlessly politicized. The film has been mischaracterized for a year and a half and we would love it if people would go and see it and judge for themselves," Boal said.

The action thriller has emerged as an Oscar front-runner after picking up multiple early awards and nominations from Hollywood groups.

FROM TORA BORA TO ABBOTTABAD

When bin Laden was killed by Navy commandos in May 2011, Bigelow was only months away from shooting a film about the failed bid to find him in the Tora Bora mountains of Afghanistan during the U.S.-led invasion a decade earlier.

She quickly revised the project.

"Zero Dark Thirty" opens not long after the September 11 attacks with graphic scenes of interrogation, including water boarding, sexual humiliation and a detainee being forced into a box.

It stars Jessica Chastain as a CIA officer called "Maya" who uses intelligence gleaned from brutal interrogations, electronic surveillance and old-fashioned spying to track down bin Laden through his use of couriers.

The opening scenes of torture, which are seen in the movie as yielding both correct and false information from prisoners, have inflamed debate in the United States.

Bigelow and Boal said the film is not meant to pass judgment - positive or negative - on such interrogation. "What we are trying to show, is that it (torture) happened. Which I think is not that controversial," said Boal.

"It's obviously an ongoing debate. It's a debate within the community of people who are experts and I am sure that debate will continue for many years," he added.

Bigelow points out that much of the second half of the film shows agents using other methods such as electronic surveillance.

The movie shifts between locations, including secret CIA centers in foreign countries known as Black sites, the Pakistan city of Islamabad and Camp Chapman, in Khost, Afghanistan. It is not meant to be an accurate depiction of all the players involved in hunting the al Qaeda leader, Bigelow and Boal said.

REAL AND COMPOSITE CHARACTERS

Instead, it tells the story through the eyes of Maya, fresh-faced and not long in the field, battling security threats, CIA bureaucracy and unsupportive bosses to eventually track bin Laden to his compound in Abbottabad, Pakistan.

"She is based on a real person, and there are other people who also contributed who are not represented, whose work I hope is reflected in her character - it's a character in a movie and not a documentary," Boal said.

"I wanted to put the audience in the perspective of those people, those men and women on the ground who are conducting this hunt," said Bigelow. "It's ten years compressed into two plus hours...But it's really the rhythm of the hunt that creates the rhythm of the movie."

Chastain told Reuters in an interview that the woman she portrays is still active. The Washington Post has reported that the agent is now in her thirties, remains undercover and while receiving the agency's highest medal, was denied a promotion.

Boal, a freelance journalist turned screenwriter who won a best screenplay Oscar for "The Hurt Locker", would not elaborate except to say that the agent was "a real person."

"I spoke to a number of people, I gathered as many first hand accounts as I could," he said. He has denied being leaked, or asking for, any classified material.

Early reviews of the film, which will be released more widely on January 11, have been positive, especially for Bigelow's sense of pacing and suspense. The Hollywood Reporter said it "could well be the most impressive film Bigelow has made, as well as possibly her most personal."

(Reporting by Christine Kearney, editing by Jill Serjeant and David Storey)

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