When the Twin Towers fell on September 11, 2001, among the thousands killed was the one man who may have known more about Osama bin Laden and Al Qaeda than any other person in America: John O'Neill.

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This 2002 FRONTLINE documentary chronicles John O'Neill's struggle to convince the FBI to pay attention to the threat posed by Al Qaeda and Osama bin Laden. The former head of the FBI's flagship antiterrorism unit in New York City, O'Neill had investigated the bombings of the U.S. embassies in Africa and the USS Cole in Yemen. For five years, he led the fight to track down and prosecute Al Qaeda operatives throughout the world. But he was a controversial figure inside the buttoned-down world of the FBI. O'Neill's critics contend that his personal failings proved fatal to his FBI career. His supporters, however, believe his main failing was refusing to conform to the standard-issue FBI mold.

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Major funding for FRONTLINE is provided by the Ford Foundation. Additional funding is provided by the Abrams Foundation; the John D. and Catherine T. MacArthur Foundation; Park Foundation; and the FRONTLINE Journalism Fund with major support from Jon and Jo Ann Hagler on behalf of the Jon L. Hagler Foundation, and additional support from Koo and Patricia Yuen.