Ron Stallworth is the first African-American detective in the Colorado Spring Police Department. One day Ron finds an ad for the KKK in the newspaper. He makes contact with the KKK by phone, claiming he is a proud white American who believes strongly in white supremacy. Eventually, the black Ron Stallworth is able to develop a telephone relationship with David Duke, the Grand Wizard of Ku Klux Klan. At the same time, Stallworth recruits a white Jewish officer named Flip Zimmerman to pretend to be Ron Stallworth and infiltrate the local KKK chapter by becoming its newest member. The black Stallworth works by phone, while the white one works from within.
Blackkklansman is adopted from the memoir, Black Klansman: race, hate and the undercover investigation of a lifetime by Ron Stallworth. The film closes with contemporary footage of the 2017 Unite the Right Rally in Charlottessville. It has been 40 years since Stallworth managed to infiltrate the KKK; the film serves as a reminder of the racist hatred that still divides.