LISTEN: Black detective describes infiltrating the KKK — and getting the 'Klan handshake' from David Duke

Now the subject of a book and a Spike Lee movie, black Colorado detective Ron Stallworth described his experience infiltrating the Ku Klux Klan in the late 1970's — an operation that led him to become the "Black Klansman."

"My job as an intelligence officer, detective, was to monitor any subversive activity which could negatively impact the city of Colorado Springs," Stallworth told NPR in a recent interview. "And, let's face it, the Ku Klux Klan historically is a subversive group. ... And when I saw the ad in the newspaper, obviously I perked up to this fact and set about trying to address it, to understand it."

The former detective told NPR that his experiences growing up hearing racial slurs hurled at him helped him play the part over the phone.

"I said I wanted to join because I was a pure, Aryan, white man who was tired of the abuse of the white race by blacks and other minorities," Stallworth recounted.

He commissioned a friend and undercover narcotics officer identified in his memoir as "Chuck" to pose as the white "Ron Stallworth" when meeting up with Ken O'dell, a soldier at a nearby base.

"He was not — none of these guys were, as I say in my book, the brightest light bulbs in the socket," Stallworth explained. "Because if they were, they would have known that they were talking to two different people — one on the phone and one in person — because my voice and Chuck's voice sound nothing alike. But they never picked up on it in seven and a half months of phone conversations and periodic face-to-face meetings with Chuck."

At one point, the detective was assigned to former KKK grand wizard David Duke's security detail when he was in town for a "publicity blitz." Stallworth described the onetime hate group leader as "very cordial," and said that unbeknownst to Duke, he understood the secret Klan handshake he gave him.

"He gave me the Klan handshake — he didn't know that I knew it was the Klan handshake, but he did give it to me," Stallworth said in the interview. "If you shake a person's hand and you extend your index and middle finger along their wrist and as you're pumping their hand you start pressing your fingers in their wrist area, it's the Klan handshake."

Listen to the entire interview below, via NPR: