Years before Osama bin Laden became a household name, a group of female analysts at the CIA was so determined to find and stop the terror leader that one said she was once counseled by an Agency superior that she was spending "too much time" on the bin Laden hunt.

"They said we were obsessed crusaders, overly emotional, using all those women stereotypes," said former CIA analyst Cindy Storer in the new HBO documentary "Manhunt," which debuted earlier this month. "Yes, we were borderline obsessed, but I thought it was for a good reason… How can you do something like this without passion? You can't."

Then the terror attacks of Sept. 11, 2001 happened - suddenly everyone was passionate about finding bin Laden.

Based on the book by national security journalist Peter Bergen, "Manhunt" features interviews with more than a dozen key players in the decade-plus-long race to catch the world's most wanted man, both before and after the Sept. 11, 2001 terrorist attacks.

Much of the beginning story focuses on what the documentary calls "The Sisterhood," a group of female CIA analysts that often worked alongside Alec Station, a CIA operations unit organized in the mid-1990s dedicated to tracking Osama bin Laden and his connection to an emerging terrorist organization called al Qaeda.

"At the time, the people who had all the deep expertise in al Qaeda were women," CIA analyst Susan Hasler says.

Nada Bakos, a former CIA analyst who later worked with the women, told ABC News that it was unintentional that so many women happened to be involved. Before Sept. 11, she said, counter-terrorism was "not a typical topic to be working on."

"For some reason, that group of women started on it early," she said.

One of the original analysts, Gina Bennett, wrote the first report on Osama bin Laden for the U.S. government, Bakos said. Storer wrote the first warning about al Qaeda for the President, according to the documentary - both documents circulating well before Sept. 11, 2001 terrorist attacks.

In the film, the women discuss their work prior to and then their reaction to Sept. 11 - the guilt for not having been able to prevent it and the frustration with other U.S. government officials saying the Agency had failed to sound the alarm, despite their repeated warnings.

The documentary then follows different Agency and some military players through the years before bin Laden's death at the hands of U.S. Navy SEALs in Abbottabad, Pakistan, including the capture of high-level al Qaeda commanders, the use of enhanced interrogation and the key to it all: the identification of bin Laden's courier.

As he has done before several times, the former head of the CIA counter-terrorism center, Jose Rodriquez, staunchly defends the use of enhanced interrogation techniques.

"You can't argue with success," he says in the film.

RELATED: Dodging 'Torture,' CIA Director Calls Waterboarding 'Reprehensible'

'You Don't Get Abbottabad Without Khost'

The documentary also discusses the December 2009 suicide bombing in Khost, Afghanistan that claimed the lives of seven CIA officers, including an original member of the Alec Station, Jennifer Matthews. In that case, the CIA believed they were meeting with an al Qaeda informant who turned out to be a double agent, sent to attack America's intelligence agency. The Agency and base security reportedly did not search the man for potential weapons before allowing him past multiple check points.

Former CIA Director Michael Hayden, who left the post ten months before the attack, said that without Khost, "You don't get Abbottabad."

"There was some criticism of the Agency, frankly I understand that. But you don't get Abbottabad without Khost," Hayden says in the documentary. "An agency that's not willing to take the risks that were evident at Khost, and which unfortunately ended tragically. That agency, if it's not willing to do what it had to do to build that trail all the way to Abbottabad."

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