(CNN) -- World War II was over, but as the 1940s gave way to the 1950s, a new evil lurked in the land.

The cover of David Hajdu's "Ten-Cent Plague," shown here, was drawn by Charles Burns.

It attracted a youthful audience -- boys, mostly -- who fell victim to its colorful images, dripping in red, and gave money to its purveyors.

Authorities took notice. The United States had a new menace, they said, one whose name started with "c" and whose first syllable rhymed with "bomb."

Comic books.

"The country was fixated on this," said David Hajdu, author of the recently released "The Ten-Cent Plague" (Farrar, Straus & Giroux), a history of the era.

These weren't just any comic books, the ones filled with the derring-do of superheroes. These had names such as "Tales from the Crypt," "Shock SuspenStories" and "Justice Traps the Guilty," and they told stories of crime and horror. Their cover images included alluring women (often in low-cut outfits), decaying corpses and spooky, murky swamps.

Hajdu, who wrote "Positively Fourth Street" about the early-'60s folk music scene, observes that when we think of postwar pop-cultural rebellion, what comes to mind is rock 'n' roll and Marlon Brando. But comic books, he notes, came first. Hundreds of millions sold every month, at 10 cents a throw.

"Everybody read comic books. They were the most popular form of entertainment in America," he said.

The fact that such entertainment was primarily aimed at children and teens raised the ire of authorities, including social scientists, newspaper columnists and political leaders. These works, they believed, were causing crime and degeneracy. They had to be stopped.

Towns hosted bonfires to rid themselves of comics; congressional hearings about the issue helped burnish the image of Tennessee's Estes Kefauver, who had led hearings against organized crime.

Comic books had been attracting concern since they were introduced in the 1930s -- and superheroes weren't immune. Figures such as children's author Sterling North and a Catholic bishop, John Francis Noll, protested the medium as glorifying crime and corrupting youngsters. The fervor dulled during World War II but came back with a vengeance afterwards as news focused on an alleged increase in juvenile delinquency.

The anti-comics movement really caught fire with the work of psychiatrist Frederic Wertham, who wrote a book, "Seduction of the Innocent," linking comics with delinquency. Sidebar: Were comics that violent?

In recent decades, Wertham has become a figure of mockery for his theories (he called the relationship between Batman and Robin "like a wish-dream of two homosexuals living together"), but Hajdu says he wasn't a cardboard villain. He was committed to working with minorities -- he ran a free clinic in Harlem -- and he genuinely cared about young people.

"He was misguided and used utterly fallacious methods, but what he was getting at was understandable," Hajdu said, though adding that "he did much more harm than good."

Among Wertham's adversaries was William M. Gaines, son of comics pioneer Max Gaines and the owner of EC Comics. Thanks to a staff of innovative writers and artists -- including Al Feldstein, Harvey Kurtzman, Wally Wood, Will Elder and Jack Davis -- and a deep investment in the crime and horror genres, Gaines revived a moribund EC, making it one of the business's most successful companies. Its titles, including "Crypt" and "SuspenStories," were both graphic and groundbreaking. See some of the covers that turned heads »

"EC Comics out-bloodied them all but also used social commentary and had a lighter quality of gruesome art," said Bill Svitavsky, a history professor at Florida's Rollins College who teaches a course on American graphic publishing with his colleague Julian Chambliss.

"EC had statements about racism and conformity to small-town values," Chambliss said. Many of EC's staffers, he observes, were World War II veterans who'd seen their share of violence, and their art -- if graphic -- gave their stories the ring of truth. (Author Grant Geissman put together a collection of EC's work, "Foul Play!" (HarperDesign), in 2005.)

However, the keepers of the boundaries pushed back, Svitavsky says. In those Red Scare times, "Adults were fearful [of works that questioned the establishment.] ... Comic books were believed to be an underestimated, unpatriotic tool to get at kids."

The children, Hajdu says, illustrated the tension of the times. Some had tried to hide their collections; others had energetically taken part in comic-book burnings. He interviewed many of them, now grown-ups in their 60s or 70s. "It was harrowing to listen to them," he said.

The issues came to a head at the subcommittee hearings on juvenile delinquency, which began in late 1953. Among the witnesses were Gaines and Wertham, who "looked as if he had come straight from doing scientific work," Hajdu writes. The comics' fate was sealed when Gaines, in televised testimony, attempted to defend a "Crime SuspenStories" cover, depicting the hand of a killer clutching a woman's severed head, as "good taste." Audiences were shocked; opinion leaders raged.

A comics publishers' association put together the Comics Code Authority, which banned the words "horror" and "terror" from comic books. Sales plunged, dozens of artists lost their jobs, and comic books didn't make a comeback for years.

"Everybody was cautious in the '60s," noted Ron Goulart, author of "Good Girl Art," a history of female images in comic books. He credits the horror-crime scare with "probably help[ing] resurrect superheroes," particularly the new breed created by Marvel Comics in the '60s.

The horror and crime books were also reflective of a changing world. Film historians have observed that the heyday of film noir was in the late '40s, and it wasn't long before Brando, James Dean, Elvis Presley and many others were busting boundaries in other genres.

Gaines was a part of that, Hajdu observes. There was one comic, a humor book, he had protected. He made it a magazine to save it from the Comics Code Authority and refused to accept advertising.

In time, the magazine became one of the most influential publications of the 20th century, inspiring generations to question authority and mocking the pieties of politics, religion and popular culture.

It was called Mad.