In 1971, Norman Mailer Head-Butted Gore Vidal.

In the red corner, novelist, essayist, name-dropper, and sniper wit with a full magazine of bons mots: ”Blood and Gore” Vidal! And in the blue corner, with an ego weighing in at 350 pounds, that megalomaniacal maven of masculinity, the bellicose belletrist: Norman ”The Maelstrom” Mailer! Ding! Ding! Ding!

Okay, no bell was rung, but that might well have been the windup to the Dec. 15, 1971, episode of The Dick Cavett Show, which featured one of the greatest bouts between two American literary heavyweights ever televised. With Cavett as referee, a riled Mailer and a baffled Vidal went 12 rounds over an essay the latter had written in The New York Review of Books in which he lambasted Mailer’s positions on women’s lib and even lumped him in with the violently misogynistic Charles Manson. The incident has been brought back into the spotlight in all its hot-under-the-collar glory in HBO’s The 50 Year Argument, the new documentary from Martin Scorsese (codirected by David Tedeschi) about the esteemed periodical and its history of intellectual contention. (The film premiered on Sept. 29.) ”The Review really is an argument that’s been going on for 50 years,” says Scorsese. “It’s an ongoing conversation, and sometimes it gets heated.”

The Mailer/Vidal prizefight is only one example among many in the movie, but it’s electrifying, and a perfectly preserved relic from an age when highbrow celebrities could occupy a significant space in the mainstream cultural conversation. (Even if it was ironic that the conversation dealt with issues to which these two men — a patriarch and a patrician — had little claim.) ”I had to wait a week to see it on air,” says Cavett. His producers wanted to make sure the episode was properly feted. ”We were promoting it like a fight.” It was. One that had started months earlier.

By the late 1960s, Mailer and Vidal had become larger-than-life figures. Mailer, a self-hyperbolized man’s man, had long raised the ire and eyebrows of feminists with demeaning portrayals of women in his essays and novels (including 1965’s An American Dream), not to mention his 1960 stabbing of his wife Adele. The women’s liberation movement, meanwhile, was a raging storm, and Mailer a 50-foot lightning rod. In response to feminist criticisms (specifically those in Kate Millett’s influential 1970 book, Sexual Politics), Mailer wrote the tract The Prisoner of Sex and participated in a combative discussion in New York City in April 1971. At this debate, also depicted in Argument, he sparred with powerhouse feminists, among them Betty Friedan, Germaine Greer, and Susan Sontag, and memorably bellowed, ”I’m not going to sit here and listen to you harridans harangue me.”

Vidal, by extreme contrast, was a member of the liberal elite who had scandalized the intelligentsia as far back as 1948 with his novel The City and the Pillar, about a gay male romance. Over the decades he had evolved into a lauded historical novelist but hadn’t lost his edge. His 1968 satire of the film business, Myra Breckinridge, featured a transgender protagonist. Two months after Mailer’s ”harridan” showdown, the NYRB published Vidal’s ”In Another Country,” a review of feminist theorist Eva Figes’ Patriarchal Attitudes in which he said that Mailer’s analysis of gender politics ”read like three days of menstrual flow.” He went on to contend that Mailer, Manson, and Henry Miller were men who viewed ”women as at best, breeders of sons; at worst, objects to be poked, humiliated, killed.”

Those words hit harder than Vidal had perhaps anticipated. ”I think Gore had written that thing about Manson as something that just occurred to him,” says Robert Silvers, editor of the NYRB since its 1963 inception and sole editor since the 2006 death of his colleague Barbara Epstein. ”I don’t think he made a big point of [Mailer and Manson] having any major kind of connection or alliance. But Norman clearly didn’t take it that way.”

Clearly. He steamed and steamed until he finally blew his stack five months later when he came face-to-face with his foe on Cavett’s show. Backstage, an alcohol-primed Mailer head-butted Vidal. (It was a favorite move.) The mood didn’t improve once the cameras started rolling. ”I knew we were in trouble when Norman entered,” says Cavett. ”He had his pugilistic walk and looked a little pissed, in the British sense.” The guests traded barbs over the article, and an increasingly recalcitrant Mailer began ranting semi-eloquently. (Mailer: ”It hurts my sense of intellectual pollution.” Vidal: ”Well, as an expert you should know about that.”) Cavett and a third guest, journalist Janet Flanner, contributed quips from the sidelines, including the host’s improvised rejoinder to Mailer regarding Cavett’s sheet of questions: ”Why don’t you fold it five ways and put it where the moon don’t shine?”

The sustained animosity surprised Cavett. ”I had had dramatic walk-offs and even had a man die on my show by that point, but this was unique. It’s almost like a well-made play,” he says. At one moment, Mailer stood up and stomped over to Vidal, who put up an arm in defense. ”There was an audible breath-catch from the audience,” says Cavett. No punches were thrown — Mailer was only grabbing Vidal’s copy of the offending article — but six years later Mailer got another chance and hit Vidal square in the face with a liquor glass at a well-attended cocktail party.

The squabbling may seem childish — indeed, at times, Mailer resembled a fuming kid on the playground — but when combined with their sizable intellects and dialectic dexterity, it makes for gripping television of the kind that doesn’t really exist anymore. ”Back then there was wonderful stuff with William F. Buckley, David Susskind, so many personalities on television at that time, including these contributors to the NYRB who were intellectual superstars like Mailer, Vidal, Sontag,” says Scorsese. ”There are fisticuffs everywhere nowadays, I just don’t know if they’re intellectual. That’s the difference.”

Mailer and Vidal would eventually reconcile before Mailer’s death in 2007, even discussing the episode in a joint interview in 1990. (For their myriad polar differences, the men also had plenty in common, including, apparently, that both claimed to have sat on Truman Capote. That’s a club with limited membership.) But their public confrontation on The Dick Cavett Show remains a thrilling cultural snapshot. ”It’s not enviable being caught between those two,” says Cavett. ”But all I was thinking was ‘Boy, this is going to be extraordinarily good television even if it’s no fun for me.”’