"The Ku Klux Klan" tells the story of America's oldest and largest homegrown terrorist organization. It is a revealing look at the philosophies and methods of a secret society that used religious symbols, secret codes, and the cloak of anonymity to bind its members together in the cause of violent racial warfare.

"The Ku Klux Klan" encompasses the organization's entire history, from its post-Civil War founding by Nathan Bedford Forrest, to its high watermark in the early 20th century, with membership swelling to four million and its founders portrayed as heroes in the film, "Birth of a...