The Klansmen were furious.

Dozens of them had congregated in a nondescript room in Atlanta, shaking cloaked heads at the worrisome news that their sect leader had just shared: An act of gross subterfuge had transpired over the airwaves. Millions of Americans had now become privy to their policies, their rankings, their closely guarded methods of organized hatred.

All of it fodder for some comic book radio show. Their mission had been compromised, sacrificed at the altar of popular culture. Kids, one Klansman sighed. His kids were in the streets playing Superman vs. the Klan. Some of them tied red towels around their necks; others pranced around in white sheets. Their struggle for racial purity had been reduced to a recess role play.

Stetson Kennedy listened, doing his best to give off irate body language. He scowled. He nodded. He railed.

The covert activist waited patiently for the Klan to settle down. When they did, he would call radio journalists Walter Winchell and Drew Pearson, offering the results of his infiltration into the group for public consumption.

He’d also contact Robert Maxwell, producer of the Superman radio serial. Maxwell, eager to aid the humanitarian mission of the Anti-Defamation League, would promptly insert the leaked information into his show’s scripts. In between fisticuffs, his cast would mock the KKK’s infrastructure, and the group’s loathsome attitudes would be rendered impotent by the juvenilia.

The Klan roared, demanding revenge on their traitor. “Show me the rat,” their leader said, “and I’ll show you some action.”

Kennedy cheered, just as they all did.

And when he returned home, his Klan robe would be traded for a cape.

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Kennedy, born in 1916, was an unlikely undercover operative. After a back injury kept him out of World War II, the Jacksonville, Florida native decided he wanted to combat anti-American forces on the home front. With Klan members alleged to have assaulted his family’s black maid when he was a child, the Klan—once again gathering steam in an era of segregation and racial divisiveness—was a favored target.

Having convinced a “Klavern” in Atlanta, Georgia that he shared their bigoted views, Kennedy donned the ominous attire of a Klansman, attended cross burnings, and covertly collected information about the group that he would then share with law enforcement and media. Radio journalist Drew Pearson would read the names and minutes of their meetings on air, exposing their guarded dialogues.

Revealing their closed-door sessions was a blow—one that Kennedy didn’t necessarily have to confine to nonfiction. In 1946, Maxwell, who produced the Superman radio serial broadcast around the country, embraced Kennedy’s idea to contribute to a narrative that had Superman scolding the racial divisiveness of the Klan and airing their dirty laundry to an enraptured audience.

“The law offices, state, county, FBI, House Un-American Activities Committee, they were all sympathetic with the Klan,” Kennedy said later. “The lawmen were, ideologically at least, close with the Klansmen. The court of public opinion was all that was left.”

Ostensibly aimed at children, Superman’s daily radio dramas were often broadcast to assembled nuclear families; one phone poll showed that 35 percent of its audience was composed of adults.

But regardless of whether parents listened, the activist believed the younger demographic was worth attending to. “Even back in the ’40s, they had kids in the Klan, little girls dressed up in Klan robes at the cross burnings," Kennedy said. "I have photos of an infant in a cradle with a complete Klan robe on. It seemed like a good place to do some educating.” 

In “Clan of the Fiery Cross,” a 16-part serial airing in June and July of 1946, Superman opposes an organized group of hatemongers who target one of Jimmy Olsen’s friends. Exploring their network, Clark Kent uncovers their secret meetings and policies before his alter ego socks the “Grand Scorpion” in the jaw. The idea, Kennedy wrote in his account of his work, The Klan Unmasked, was to made a mockery of their overblown vernacular.

When traveling, for example, Klansmen might identify one another by asking if they “knew Mr. Ayak,” an acronym for “Are You a Klansman?” Although Kennedy may not have actually shared their code words on air—a longstanding myth that was debunked in Rick Bowers’s 2012 book, Superman vs. the KKK—their histrionics were perfect for dramatization in the breathless structure of a radio drama. Given shape by actors and sound effects, all the clubhouse tropes of the Klan seemed exceedingly silly.

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As Kennedy continued to serve up Klan secrets to Superman, he watched as Klan morale dipped and membership enrollment ebbed. Desperate, the Klan tried calling for a boycott of Kellogg’s, a new sponsor of the show, but racial intolerance was no match for the appetites of post-World War II homes. Rice Krispies and Corn Flakes remained breakfast table staples, and Superman’s battles with the close-minded continued. Emboldened by his success against the Klan, Superman took aim at Communism, a favorite target of the show’s anti-Red star, Bud Collyer.

Kennedy would go on to burden the Klan using proof of uncollected tax liens, and eventually convinced the state of Georgia to revoke their national corporate charter.

Kennedy died in 2011 at the age of 94. While some of his accounts of subterfuge in the Klan later came under fire for being embellished, his bravery in swimming with the sharks of the organization is undeniable. So, too, was his wisdom in utilizing American iconography to suffocate prejudice. Fictional or not, Superman may have done more to stifle the Klan’s postwar momentum than many real people who merely stood by and watched.

Portions of this article were excerpted from Superman vs. Hollywood: How Fiendish Producers, Devious Directors, and Warring Writers Grounded an American Icon by Jake Rossen with permission from Chicago Review Press. Copyright (c) 2008. All Rights Reserved.