(CBS) — Spike Lee’s latest movie, “BlacKkKlansman,” tells the true story of Ron Stallworth, a black cop who infiltrated the Ku Klux Klan and duped its Grand Wizard David Duke. He was also asked to lead one of the KKK’s local chapters.

Stallworth joined “CBS This Morning” on Friday along with Lee to discuss the film.

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He brought along his official 1979 KKK membership card, which he still carries as a “memento” of his career.

The idea for the movie began when Jordan Peele called director Spike Lee and pitched him the story in a just a few words: “Black man infiltrates KKK.” Stallworth wrote a book about his experience in 2014, but Lee had never heard of it.

The real story started when Stallworth, the first black officer in Colorado Springs, was scanning the newspaper and came across an ad for the Ku Klux Klan along with a P.O. Box number.

(Credit: CBS)

“We scanned the newspapers every day to see what might impact our city and what if anything we can do to respond to it. … I pinned this note identifying myself, basically as a white supremacist who wanted to affect the white cause. Then I made a mistake and signed my real name. …I put it in the mail, forgot about it,” Stallworth said.

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About a week or two later he got a phone call. At that point, Stallworth said he didn’t have a plan in mind but on that call began to describe a white officer about the same build as him.

Stallworth went on to forge a relationship by phone with the KKK chapter and even attended events where he could hide his race under the white supremacist organization’s signature hood. Whenever face-to-face meetings were unavoidable, that white officer he described would stand in.

Lee has written, directed and produced dozens of acclaimed moves over his more than 30-year career, but critics are calling “BlacKkKlansman” his best in decades.

The issues addressed in the film aren’t new territory for Lee, who has been challenging views on race relations in America since his iconic 1989 film “Do The Right Thing.” Though based on true events, it was important to Lee to diverge from the real story at times in order to make an impact.

“We felt that if this film was going to connect, we would have to put stuff in it that will make affect you and everybody else. … This does not want to be a PBS documentary and that led to the coda of the movie,” he said.

Stallworth couldn’t go public with his story until much later, but believes if he had, KKK Grand Wizard David Duke might not have become as powerful as he did.

“Simply because he would have had to answer to the people he was trying to appeal to, why he got conned by a black man. I feel like had I been allowed to go public with this, we might have been able to impact that, we’ll never know. But I like to think that we might have,” Stallworth said.

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