When Bob Guccione launched Penthouse with a bank loan in 1965, he aimed to publish a magazine that highlighted explicit photos of women – a direct competitor to Playboy.

The porn mogul, at one point one of the wealthiest people in America, lost his entire fortune before he died in 2010 at age 79. He’s now the subject of a new docuseries on A&E called "Secrets of Penthouse," which details his rise to stardom and financial downfall. It features new interviews with two of his children, his nephew as well as several Penthouse "Pets" and former Penthouse executives, among others. Many of the subjects featured in the series have never publicly spoken out before, the network noted. The first part aired Monday with the second premiering Tuesday night.

"My father was involved with this very controversial, groundbreaking business," Guccione’s son, Nicholas Guccione, told Fox News Digital. "At a very young age, I didn’t quite grasp it as I was growing up in England. But when we moved to America, it hit me like a ton of bricks."

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A side-by-side photo of Bob Guccione and Hugh Hefner with their models

Bob Guccione, left, whose Penthouse magazine was a direct competitor to Playboy founder Hugh Hefner, is the subject of "Secrets of Penthouse." (Getty Images / File)

The Brooklyn-born Guccione spent several months in a Catholic seminary before dropping out to pursue his dream of becoming an artist. He headed to London in 1960 where he began photographing models. Guccione was working as a cartoonist and a manager of self-service laundries where he got the idea of launching an adult magazine that would cater to "regular guys."

A young Bob Guccione in a suit

A young Bob Guccione is shown in London circa 1965. (Daily Express / Hulton Archive / Getty Images / File)

"People attacked us," Nicholas said. "We’ve been attacked by many entities from many sides. … And it’s pathetic. These moral guys are the ones you want to watch out for, not us. We’re like dentists. We say, ‘I’m going to drill your tooth. It’s going to be loud. It’s going to hurt. But at least you know what you’re getting.’ These guys, on the other hand, hide like wolves in sheep’s clothing. But us, we tell it like it is."

Bob Guccione taking a photo

Bob Guccione looks through the viewfinder of a camera circa June 1977. (Bob Guccione / The OG Collection / Getty Images / File)

Nicholas said his father and Playboy founder Hugh Hefner "were on the same team."

"There was no animosity whatsoever," he said. "We wanted to showcase the beauty of the female form through beautiful photography. And we were both part of the sexual revolution [in America]."

"I met Hugh Hefner purely by chance when I lived in Los Angeles in the ‘90s," Nicholas said. "He was very cordial, had no entourage. We were in a little hole in the wall on Sunset Boulevard, a strip club. … He was on his own, just like me. … We were both on the same team and we knew it. And we wanted to break new ground."

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The same couldn’t be said about Hustler’s Larry Flynt.

"He was a different animal," Nicholas chuckled. "They took it one step further than Penthouse. At one point, they published a cover of a woman going through a hamburger meat grinder and coming out as ground meat. Now that’s disgusting. We weren’t close with Hustler and Flynt. They were a little bit skewed. But as far as Playboy and Penthouse, I think we both had a wonderful and healthy representation of lovely ladies showing off their beauty."

A Penthouse model wearing all black

American model and actress Victoria Lynn Johnson poses for Penthouse magazine circa 1977. (Bob Guccione / The OG Collection / Getty Images / File)

By 1982, it was reported that Guccione had a net worth of about $400 million. In 1979, he invested $17.5 million in the X-rated film "Caligula." The film about the decadent Roman emperor starred Malcolm McDowell, Peter O’Toole and Helen Mirren. The movie was widely panned by critics for its hardcore sex scenes and depictions of graphic violence.

British actors Malcolm McDowell, as Caligula, and Teresa Ann Savoy as Drusilla

British actors Malcolm McDowell and Teresa Ann Savoy star in "Caligula," directed by Tinto Brass. (Silver Screen Collection / Getty Images / File)

Guccione’s family took a hands-on approach to running Penthouse, with several of them being on the staff. And there was one rule everyone, including Nicholas, had to follow.

"Don’t f--k with the Pets," he said, referring to the magazine’s pinups. "He also told the Pets, ‘Don’t go near my sons.’ But it was like growing up in a candy store and saying, "Nick, you see those candy canes? Don’t go near them. Don’t even look at them.’"

"Well, that didn’t last long," he chuckled.

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Nicholas Guccione kissing his then wife Niki

Nicholas Guccione is seen here with then-wife and Penthouse Pet Nikie St. Gilles. They divorced in 2010. (Ron Galella Ltd. / Ron Galella Collection via Getty Images / File)

Nicholas went on to marry Penthouse Pet Nikie St. Gilles, in 2000. They welcomed a son in 2001. The couple divorced in 2010, but they remain close.

"Closer now than we were even when we got married," he said.

The rule didn't apply to Guccione. He had no qualms about mixing business with pleasure. His daughter, Nina, says in the docuseries that their father made the models take contraceptive pills.

Jenna Jameson wearing a light blue tank top

Jenna Jameson, who spoke out in "Secrets of Penthouse," is the magazine's most famous "Pet." (Adrianne Olivera Lacroix / FilmMagic / File)

"He would say it makes the girls look more voluptuous before a shoot," she said. "But it occurred to me that he was probably trying to prevent the girls from getting pregnant. It’s disgusting. But he didn’t care."

Vanessa Williams wearing a sparkling red dress and crown

Penthouse stirred headlines in 1984 when nude photos of Vanessa Williams appeared in the magazine. (NBCU Photo Bank / NBCUniversal via Getty Images / File)

Penthouse stirred headlines in 1984 when nude photos of Vanessa Williams appeared in the magazine. The racy snaps were taken two years before she became the first Black Miss America and were rejected for publication by Playboy, according to the New York Times. Williams was forced to relinquish the crown. The issue sold nearly 6 million copies and reportedly made $14 million. She sued for $500 million.

The suit was dropped. Williams went on to launch a successful career in music and film.

In 2015, the CEO of the Miss America organization issued a formal apology to Williams. The 60-year-old, who didn’t participate in "Secrets of Penthouse," didn’t immediately respond to Fox News Digital’s request for comment.

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Vanessa Williams wearing a light brown sleeveless dress

Vanessa Williams received a formal apology from Miss America in 2015. (Ida Mae Astute / Disney General Entertainment Content via Getty Images / File)

Nicholas said his father didn’t have any regrets about the controversy.

"I was young, but I do remember we made so much money from that one issue," he explained. "And my dad, he was a simpleton. He liked to play video games in his bedroom. I didn’t see him for years because he was too involved in his own things. … He got lucky for having a good eye for beauty. … People would go, ‘You grew up with Penthouse – you must abuse and use women.’ Quite the opposite – I respect and love women, that’s what I learned from growing up in this industry. I have no issues with the past models. … We had a professional organization shooting women."

Success as a publisher allowed Guccione to amass an impressive art collection, which included paintings by El Greco, Modigliani, Dali, Degas, Matisse and Picasso. The works adorned his 30-room, 22,000-square-foot mansion in New York City.

But Nicholas admitted that his father was a lousy businessman.

Bob Guccione wearing a gold and blue plaid blouse

Penthouse Magazine Publisher Bob Guccione is seen here at home in front of a painting by Modigliani called "Boy with Red Hair," which was valued at an estimated $11 million. (Steve Azzara / Corbis via Getty Images / File)

A $200 million Penthouse casino in Atlantic City never materialized, the New York Times reported. Guccione never obtained a gambling license, which caused construction to stall. Guccione lost much of his investment as legal fees quickly mounted. Then in 1985, the IRS demanded $45 million in back taxes. In 1986, a federal anti-pornography report resulted in newsstands and convenience stores pulling Penthouse from their magazine racks. Circulation further dropped. In 1992, Guccione had to borrow $80 million to cover another tax bill, the outlet revealed.

Corinne Alphen looking at a window away from the camera

Corinne Alphen poses for Penthouse circa 1981. (Bob Guccione / OG Collection / Getty Images / File)

As pornography became more accessible online in the ‘90s, Guccione attempted to deliver more explicit content, which drove many advertisers and vendors away. More bad investments were made. As debts continued to soar, Guccione sold many of his prized artworks and properties. 

According to the Audit Bureau of Circulations, Penthouse's circulation dipped below 1 million in the late 1990s and fell to about 463,000 in 2003, the year General Media Inc. filed for bankruptcy. Over the first six months of 2010, Penthouse reported circulation of barely 178,000. In 2004, a private-equity investor from Florida acquired Penthouse in a bankruptcy sale.

Guccione's financial problems forced him to give up his prized art collection in 2002. The collection was appraised by Christie's for $59 million. He also had to give up his Manhattan mansion.

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Bob Gucciones New York City mansion

Bob Guccione's Penthouse Mansion is seen here Aug. 13, 2003, in New York City. At the time, he was in danger of losing his home. (Mario Tama / Getty Images)

"My dad made half a billion dollars in the ‘80s and thought he could do no wrong," Nicholas said. "But he was surrounded by sharks that wanted to take a bite out of him. He listened to the wrong people and believed in them."

Nicholas remembers the last time he saw his father. The patriarch was at Plano Specialty Hospital in Texas battling lung cancer.

"He was on his deathbed with tubes up his nose," said Nicholas. "And then not long after, he was gone."

A young Nicholas Guccione in a grey t-shirt being embrace by his father in a grey tank top

A young Nicholas Guccione, left, with his father. (A&E)

Over the years, Nicholas has devoted himself to fatherhood. He’s also writing a book.

"It’s a shame what happened because Penthouse had a lot of potential," he said. "My dad screwed up when he started going into … hardcore pornography. … And the stuff that’s out there now? It’s disgusting. … The fact that my dad went broke is unfortunately proof that he didn’t have a good handle on what he was doing. … But my dad was just a photographer with a good eye who got lucky."

"Secrets of Penthouse" airs Sept. 5 at 9 p.m. and will be available for streaming in full the following day. The Associated Press contributed to this report.