In late 1975, or early 1976, Malcolm McDowell received a call from Gore Vidal. Vidal, who was, as ever, witty, wildly entertaining, slightly dangerous, and very persuasive, wanted to know if McDowell would be interested in playing Caligula, the young Roman emperor who declared himself a god, named his horse imperial consul, and was known to execute advisers that forgot his birthday.

“He wanted something from me, so he was extremely nice,” McDowell recalls. “Especially at the start of the whole thing.”

When McDowell asked who would be paying for the movie, Vidal invited him to lunch at London’s Penthouse Club, where he revealed that the producer was Bob Guccione, the founder and publisher of Penthouse magazine.

“The pornographer?,” McDowell asked.

“Just think of Bob as one of the Warner brothers,” Vidal replied.

By the second day of shooting, McDowell says, “I realized it wasn’t the movie I’d signed up for.”

Caligula, which created its own cinematic genre by combining the sweeping historical epic with high-end pornography—not to mention incest, decapitation, castration, and necrophilia—inspired, upon its 1979 release, a critical revulsion very possibly unmatched in the annals of moviemaking.

Newsweek described it as “a two-and-a-half-hour cavalcade of depravity.” Roger Ebert walked out, “disgusted and unspeakably depressed,” but not before overhearing a fellow moviegoer describe Caligula as “the worst piece of shit I’ve ever seen.” Not to be outdone, Variety called Caligula “a moral holocaust.”

Malcolm McDowell as the titular Roman emperor in a scene from the film. By the second day of shooting, he says, “I realized it wasn’t the movie I’d signed up for.”

But when the movie became the subject of an obscenity trial in Boston, it won an unexpected seal of approval from a former Harvard dean and classics expert who had been asked to testify. “I’m not arguing that it’s a great movie,” he told the court, “but as far as the historical side is concerned, it is exact.”

The most memorable description of the film, however, comes from Dame Helen Mirren, who played Caligula’s wife, Caesonia. Caligula, Mirren said, is “an irresistible mix of art and genitals.”

“People ask me, ‘Oh my God, how could you do that?’ But I’ve never regretted it for a moment,” she says. “It was kind of terrible—and kind of wonderful.”

The Original Anarchist

Caligula began as a 1972 treatment by Italian director Roberto Rossellini. Rossellini’s goal was historical accuracy. He wanted to make a film that showed the rarely seen poverty and squalor of ancient Rome, as well as the splendor enjoyed by its mad ruler.

Rossellini’s nephew Franco gave the treatment to Vidal, who had written the best-selling novel Julian, about the Roman emperor Flavius Claudius Julianus, and had contributed to the script for Ben-Hur. Vidal was immediately sold on the idea and began devouring translations of second-century biographies of the emperor. As he began to conceive it, the film would offer an answer to the question “What happens when you take a normal young man and give him life-and-death power over everyone in the world?”

It was the kind of project that would require an ambitious, deep-pocketed producer who was unafraid to fund a controversial movie requiring elaborate sets, thousands of extras, and a high-profile cast. That kind of producer was hard to find. Vidal, however, knew someone that was perfect for the job.

A decade earlier, Guccione was a penniless artist, living in Europe. One day, while passing a London newsstand, he observed that Playboy was the only magazine of its kind. Armed with a camera, artistic instinct, and a desire to make money, Guccione decided to create a raunchier competitor.

The first issue of Penthouse sold more than 100,000 copies in just a few days and set off “the pubic wars,” in which Guccione and Playboy’s Hugh Hefner battled to see whose magazine could show more without being labeled as obscene by the U.S. government.

By 1975, Guccione was one of the richest men in America and a substantial investor in Chinatown and The Longest Yard. But, despite his success, Guccione still had unfulfilled artistic ambitions. When Vidal approached him, Guccione agreed to put up $7 million of his own money to finance the film, which he envisioned as the first part of a trilogy of historical films about the corrosive nature of power.

Penthouse publisher Bob Guccione, on the set of Caligula, which he produced.

Caligula, he predicted, would one day rank as “a cinematic landmark—a la Citizen Kane.

Vidal originally wanted cult filmmaker Paul Morrissey to direct, but with Guccione involved, bigger names entered the mix. One was John Huston, but he ended up backing out. Then there was Swept Away director Lina Wertmüller, who wanted to replace McDowell with Jack Nicholson, re-write the script, and retitle the film Lina Wertmüller’s Caligula. That was out, since one of Vidal’s contributions to the project was the air of sophistication and historical credibility his name lent to the project, then titled Gore Vidal’s Caligula.

The first issue of Penthouse sold more than 100,000 copies in just a few days and set off “the pubic wars.”

At one point, McDowell was asked about British filmmaker Nicolas Roeg and said he’d be a great choice. But once Franco Rossellini screened Tinto Brass’s erotic Nazisploitation movie, Salon Kitty, Guccione quickly decided that he’d found his director.

Charismatic and heavyset, Brass was a cigar-chomping political radical with a wicked sense of humor that endeared him to the cast, particularly McDowell and Mirren.

“He was a wonderful, Italian-papa kind of guy,” Mirren says, recalling that Brass liked to “put pepper in the ass of others—in a delightful, Italian way.”

Peter O’Toole and Sir John Gielgud joined the cast in the spring of 1976, as did Maria Schneider, who was supposed to play Caligula’s sister (and one true love) Drusilla. Still traumatized by her experience making Last Tango in Paris, however, Schneider quit Caligula on her first day, after seeing how much nudity her part required.

As casting progressed, Vidal was sending Guccione drafts of his screenplay that were extremely heavy on gay sex. Knowing this would never fly with the Penthouse audience, Guccione made revisions and other suggested changes.

“Bob was re-writing the script,” says former Penthouse publicist Leslie Jay-Gould. “Gore would send the script, and Bob would be telling him [what to do], if you can imagine Bob giving Gore notes.”

This didn’t sit well with Vidal, who appeared on the March 1976 cover of Time and, with what Guccione called “perfect Vidalian timing,” told the magazine that writers were the creative force in movies, while directors were parasites who just needed to follow the script.

Helen Mirren as Caligula’s wife, Caesonia. She later called the film “an irresistible mix of art and genitals.”

Brass responded by banning Vidal from the set, a move that got no pushback from Guccione. “Gore’s work was basically done,” he said, “and Tinto’s was about to begin.”

Brass and McDowell had meanwhile decided that they had their own ideas about how Caligula should be portrayed in the film.

“I didn’t want to play him as a madman. Where do you go with that?,” McDowell says. “So we came up with this idea of having him be the original anarchist … destroying the empire from the top.”

“A Bit Like a Fellini Movie”

Production began in August 1976 at Dear Studios, in Rome. “It was all rather absurd,” says John Steiner, who played Caligula’s adviser Longinus. “The first day we were in this huge hangar, which was a major Roman set. There must have been a thousand people there, and, at a certain point, in comes Franco Rossellini riding a white horse.”

The 64 sets and 3,000 costumes were designed by the Oscar-winning production designer Danilo Donati, a frequent collaborator of Federico Fellini’s and Pier Paolo Pasolini’s. There were also wigs crafted from 1,000 pounds of human hair; a 300-yard-long stadium; 450 gallons of blood; 5,000 pairs of shoes, boots, and sandals; a tank filled with more than a thousand gallons of pure mineral water, which had to be changed twice daily; a 175-foot-long floating ship with 120 hand-carved oars; and what can only be described as a five-story human-head mower.

“[It] was a bit like a Fellini movie—the grandiosity, the amount of people, the extras, the crazy costumes and makeup,” says actress Mirella D’Angelo, who played a virgin deflowered by Caligula on her wedding day. “It was scary in a way. There was a feeling of sensuality and violence similar to the movie.”

There were widespread rumors of on-set bestiality, pedophilia, animal slaughter—almost every unsavory activity one could imagine. The rumors, however, were exactly what Guccione had wanted when he banned visitors—particularly media—from the set and told everyone involved not to respond to—or deny—any of the allegations.

The plan was to create intrigue, infamy, and mystery around the shoot, which would crescendo just before the film was released. Any rumors, no matter how horrific, were good for business. Or so Guccione hoped.

“Hello, Johnny,” O’Toole said to Gielgud when he arrived on set. “What’s a knight of the realm doing in a porno movie?”

“Oh, Peter,” Gielgud replied. “Do you really think so?”

O’Toole, who had momentarily given up alcohol for marijuana, came to Rome for three weeks to play Tiberius, Caligula’s pedophiliac (and syphilitic) predecessor.

The charming and devilish O’Toole got on well with McDowell and the cast, but quickly assessed Brass as a lightweight, referring to him as “Tinto Zinc.” His utter and complete disregard, however, were reserved for Guccione.

“Hello, Johnny,” O’Toole said to Gielgud when he arrived on set. “What’s a knight of the realm doing in a porno movie?”

Guccione had increased his budget to $8.5 million in October, despite a growing sense that Brass was a loose cannon. Each time Guccione came to check on the production, Brass would “work within the parameters we had originally agreed [on],” Guccione said. “[But] the minute I left Rome, or even turned my back he would go thundering off on his own.”

McDowell in a scene from the film.

Perhaps Guccione’s biggest complaint was about the Penthouse models—“Pets,” the magazine called them—who arrived each day for an early call and remained on set until late at night without ever appearing on-camera. And where Guccione wanted scenes of soft-focus eroticism, Brass was doing the opposite: shooting sex scenes involving dwarves, elderly women, and a live eel.

Tensions came to a head when one of the Pets elbowed her way to the front of a long line of extras waiting to have their wigs removed and wound up getting shoved.

The next day a furious Guccione arrived on set demanding to know who’d had the audacity to push one of the Pets, and then lined up the extras so that the Pet in question could identify the culprit. Staring into each of their eyes as she walked down the line, the Pet finally pointed and screamed, “That’s the one! She’s the one!”

In response, McDowell and Brass added a scene where one character is asked to identify Tiberius’s murderer (a murder Caligula has ordered) and walks down a line of men, staring into their eyes and finally screaming, “That’s the one!”

According to McDowell, Guccione “didn’t get that it was him” and told everyone how much he loved the scene.

On another occasion, McDowell asked Brass why an upcoming scene required the entire Roman Army to be naked. Brass thought for a moment and replied, “If we don’t screw Guccione, we fail.”

“They Couldn’t Get Away with It”

After five months and two weeks of shooting, Caligula wrapped, on Christmas Eve 1976, nearly seven weeks behind schedule and $8 million over budget. Brass headed for London’s Twickenham Studios to try to edit 122 hours of footage down to two in time for the movie’s planned October 1977 release.

The crew at Twickenham would pile into the projectionist’s booth and stare at the screen in amazement at footage such as the tracking shot where O’Toole walks past a long line of naked women, all bent over. How, they wondered, was Brass going to assemble a commercially releasable film? “They couldn’t get away with it,” Stuart Urban, Brass’s editing assistant, says. “[That] was our general thought.”

Brass’s footage, however, paled in comparison with what was happening in Rome, where Guccione was sneaking back into Dear Studios—accompanied by a small crew and a dozen Pets.

“I never intended to involve myself, certainly not in the shooting,” Guccione said, “until I saw the way Brass had mishandled and brutalized the film’s sexuality.”

Despite no experience directing or using a movie camera, Guccione and his second-unit director filmed several unsimulated heterosexual and lesbian sex scenes, including an orgy on the brothel boat.

On April 18, 1977, with 40 minutes of film already edited, Brass and his crew arrived at Twickenham to find the doors to their editing hut closed and the director’s gigantic Prevost editing machine sitting outside in the snow. Brass had been fired, and Guccione was seizing creative control of Caligula.

McDowell and Mirren in Roman dress.

It was at this point that the production entered a period during which, Guccione said, “Tinto was suing us. We were suing Tinto. Tinto was suing Gore and Gore was threatening to sue everybody else.”

Citing his contractual right to final cut, Brass gained an injunction that prevented Guccione from showing any version of Caligula without the director’s consent. The result was a delay in the release that stretched into late 1978, when the toll the suit was taking on Brass’s career became too much and he agreed to settle with Guccione.

When the film was finally released, it bore no director credit. Instead, it read: “Principal Photography by Tinto Brass.”

Where Guccione wanted scenes of soft-focus eroticism, Brass was doing the opposite: shooting sex scenes involving dwarves, elderly women, and a live eel.

Then there was Vidal, who wanted his name removed from a film that bore no resemblance to his initial vision. Disgusted by what Guccione and Brass had done, Vidal relinquished his percentage of the profits and his screenplay credit.

While assembling the film with editor Nino Baragli, Guccione ran into a new problem: the need for the lead actors to re-dub much of their dialogue. Having already been paid, O’Toole repeatedly failed to show up for re-recording sessions, until the sound crew was finally able to pin him down in Canada.

“I waited until a cashier’s check came to my house for the remainder of the money,” McDowell says. “And then I went in and re-voiced it. I re-voiced the whole damn performance.”

While re-recording his dialogue, McDowell was shown a version of the film without the boat-brothel orgy or the lesbian tryst—scenes he was unaware of until he showed up unannounced at a screening in Hollywood, where he watched as Penthouse staffers called Guccione in New York to ask if they should show the film with its star in the audience.

When they finally received permission, McDowell sat and watched in horror. Scenes appeared in the wrong place. Footage was sometimes out of focus. There were random zooms, and characters who’d been eliminated from the story but showed up anyway, as well as the raunchy lesbian and orgy scenes interrupting dramatic scenes.

The scenes that had been shot by Guccione “stuck out like a sore thumb,” Mirren says.

“Sex for Sex’s Sake”

Premiering in Rome on November 10, 1979, Caligula ran for six days before officials declared the film obscene and had it pulled from theaters, providing Guccione exactly the kind of publicity he wanted.

When it arrived in New York, Caligula didn’t clear customs until after the U.S. attorney for the Eastern District held screenings in Brooklyn and Washington so government lawyers could determine if it constituted obscenity under the Supreme Court’s definition, which required a total lack of “social or artistic merit.” The film squeaked through.

One of the film’s many orgy scenes.

Not wanting the stigma of an X rating, Guccione didn’t submit the film to the M.P.A.A., instead creating his own X equivalent of MA (Mature Audiences), with no admission for anyone under 18.

The American premiere took place on February 1, 1980, at the Penthouse East Theater, in Manhattan. (Previously the Trans-Lux East, it was purchased and renamed by Guccione for the occasion.) On an extremely cold afternoon, moviegoers lined up around the block to purchase $7.50 tickets at a time when the average admission price was $3.

“It was amazing,” Jay-Gould recalls. “Even [New York Times film critic] Vincent Canby stood on line.” Guccione’s strategy of avoiding the press had worked so well that veteran Manhattan publicist Sy Presten told Jay-Gould that tickets should cost $15.00. “[Sy] knew this was going to be a blockbuster,” Jay-Gould says, “and that the controversy was going to make it one.”

By showing the film at theaters he’d rented himself—what’s called “four-walling”—Guccione ensured that all proceeds from ticket sales went straight into his own pocket. And Caligula’s notoriety continued to provide free publicity.

Most notable was a two-week obscenity trial in Boston where the former Harvard dean testified for hours about the film’s value and historical accuracy. When the judge ruled in his favor, Guccione had the phrase Almost Banned in Boston placed prominently on the marquees of theaters where Caligula was being shown.

With a final budget of somewhere between $17.5 and $22.5 million, Caligula made $21 million during its initial U.S. release and millions more in Europe and around the world. As recently as 2005, Penthouse was reportedly still selling 3,000 DVDs of the film each month.

Meanwhile, as anticipated, critics despised the film. Almost universally. “There was one good review that came out of the Midwest somewhere,” Jay-Gould recalls. “Bob didn’t expect it to be well received. That’s not what his intent was.”

Vidal compared the film to “a Copenhagen sex show” and said the sets reminded him of “the lobby of the Fontainebleau Hotel in Miami Beach.”

McDowell asked Brass why an upcoming scene required the entire Roman Army to be naked. Brass thought for a moment and replied, “If we don’t screw Guccione, we fail.”

“[Audiences] knew there was an orgy,” Jay-Gould says, “but no one knew what it was going to be. But it was … beyond anything I could ever imagine. There was no love involved, just sex for sex’s sake, and the more outrageous you could make it, the better.”

Guccione, who died in 2010 at the age of 79, always insisted that the film wasn’t just smut, noting that for the kind of money he spent on Caligula he “could have made 200 porno films”—and probably with a lot less aggravation.

The film’s sets and costumes were designed by the Oscar-winning production designer Danilo Donati.

According to his son Bob junior, Guccione “wanted so much to be acknowledged for something other than being a pornographer.”

McDowell remains proud of his performance and has always believed that there is a good movie about an anarchist emperor somewhere within the miles of footage that Brass shot. But he has always felt that the film “crossed a line.” It was “so overwhelming that reasonable people—like Academy members—were horrified by it,” he says.

The actor, however, has also come face-to-face with the irony that there are those who genuinely like the film and others that believe it’s an impeccable representation of pre-Christian Rome.

“I remember doing a movie with Colin Firth, and he’s a bit of a Roman scholar,” McDowell says, recalling that Firth told him that the film was stunningly accurate.

“It’s the only Roman movie that really catches the times,” Firth said, according to McDowell.

“O.K.,” McDowell replied. “I’ll take your word for it.”

On December 5, 1980, in a Variety story headlined CATHERINE THE GREAT WILL GET THAT CALIGULA TOUCH IN PENTHOUSE PIC, Guccione spoke of plans for the second film in his “absolute power corrupts absolutely” trilogy, which was in pre-production with a planned budget of $25 to $30 million.

After 18 months of research, the film had a great deal in common with Caligula: impeccable historical accuracy, lavish sets and costumes by Donati, and scenes of hard-core sex.

There were, however, at least two major differences.

First, Guccione was going to fund much of the film with advances from overseas distributors. But, more importantly, Guccione told the reporter that, if time permitted, he intended to direct it himself.

The film was never made, and Caligula is not available for streaming anywhere.

Josh Karp is the author of Orson Welles’s Last Movie: The Making of The Other Side of the Wind