Who Was Lee Harvey Oswald?This investigative biography examines the Kennedy assassination by exploring the enigma that was Lee Harvey Oswald. Was Oswald the emotionally disturbed lone gunman of the 1964 Warren Commission Report? Was he, as the House Select Committee on Assassinations concluded in 1979, only one of two gunmen that day in Dallas? Or was he an unwitting scapegoat for the real assassins, as Oswald himself claimed when he was arrested?

FRONTLINE's investigation examines the life and enduring mysteries of Oswald. What makes Oswald so puzzling is that by Nov. 22, 1963, he had apparent links with virtually every group that had a strong motive to eliminate President Kennedy, says William Cran, the documentary's senior producer. The big question is: Were any of those groups controlling Oswald on the day of the assassination or was he simply in the grip of his own personal confusion - the eccentric mix of political passions and emotional instability that characterized his entire life?

The result of a year-long investigation by more than a dozen reporters and expert consultants, Who Was Lee Harvey Oswald? draws upon hundreds of witnesses, in particular those who closely studied and observed him, as well as documents, photos, and video and audio recordings - many of which had never before been made public - to chronicle Oswald's life story: from his troubled childhood to his mysterious service in the U.S. Marines that raised questions about his possible connections to U.S. military intelligence.

The program also investigates Oswald's activities in the late 1950s and early 1960s, including his dramatic defection to the Soviet Union in 1959 and his return to the United States in 1962.

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