James Franco: master of sex

If you're an A-list Hollywood actor you need to have a "thing"; something beyond being just really, really good looking. For George Clooney it's politics, for Leonardo DiCaprio it's saving the tigers, Gwyneth Paltrow has her quinoa muesli, and as Mark Ruffalo's Twitter reveals, he's very much invested in the anti-fracking scene. For James Franco, though, his thing appears to be, well, everything. Once you start researching the 35-year-old's recent antics, it quickly becomes clear just how bizarrely prolific he is: he's currently making five films, with six more in post-production; he's a fervent blogger, tweeter and Instagrammer; he publishes short stories and poetry, famously penning a poem to commemorate the second inauguration of President Obama back in January; he is a sometime multimedia artist, and dressed up as Janet Leigh for an art installation based on Psycho this summer; he's directed over 20 films you've probably never seen, has a recurring role in the US daytime soap General Hospital (which he's dubbed "performance art") and this year alone featured in three mainstream Hollywood movies (Oz: The Great And Powerful, Lovelace and This Is The End). Right now, though, it seems most of his artistic attention is focused on one thing: sex.

Franco's interest in the bumping uglies, the old in-and-out, what we might call nookie, has something of an academic tone to it (he's got a masters from Columbia and a PhD from Yale, after all). In particular, he is keen to rebel against the beige treatment of sex in mainstream cinema: the soft stroking of hairless limbs, the passionate kiss that cuts to a dishevelled duvet, the straight-sex, softcore-only policies. He's a sexually frustrated man; frustrated that the world's not ready to be open about the explicit rutting we're all supposedly streaming from our iPhones.

It's a topic he addresses in a new film, Interior. Leather Bar, which reimagines a series of gay S&M scenes that were removed from William Friedkin's controversial 1980 undercover cop film, Cruising, and laces this footage with po-faced film-school analysis where the cast and Franco (who plays the part of James Franco) describe the exceedingly challenging motives behind the film. Another Franco-produced flick, meanwhile, is Kink, which focuses on Kink.com, the world's largest producer of bondage and discipline, sadism and masochism porn (also known as BDSM). It's a site that Terry Richardson has recently photographed for a feature. Let's leave it at that.

I catch up with Franco as he's driving back through LA after breakfast with a friend. It's likely the breakfast was a meeting and the friend was actually a "prospective collaborator", given that he has such a ceaseless appetite for projects. In fact, it's hard to tell where his work ends and his life begins: his ventures are often autobiographical and routinely mock gossip surrounding his sexuality.

He says it was his experience during a film course that first drew his attention to Cruising. "I went to film school," he explains, "and I started taking some critical theory courses outside of my film-making programme. One of them was queer cinema. I started to learn more about the controversy of when Cruising was made." A long, ruminating umm echoes down the phone. "There was something vital about it," he says. "There was something I wanted to engage with, and that's how a lot of creative processes start. It feels like there's a certain kind of energy and maybe you don't know exactly how to approach it in the beginning, but you know that there's something there."

'You can download Smurfs 2 as easily as you can download hardcore porn. You can have them both on your desktop in the same amount of time'

The urge to make a pornographic arthouse film – which he co-directed with Travis Mathews – came once he'd heard that the original cut of Cruising had some 40 minutes of hardcore sex cut out so that it would dodge an X-rating. Franco felt inspired by the mythology of the deleted footage, which was so extreme at the time that it caused offence to both the MPAA ratings board and the gay community. So much so that he wanted to reimagine what the lost scenes looked like.

"I figured if it was cut out to please the MPAA then it must have been pretty explicit material, so that interested me. What was it, exactly?" he asks, academically. "I started getting into that. I did speak to William Friedkin; he would film in [the actual leather bars], and I guess they were having sex and doing a lot of things, and that's the 40 minutes."

He cuts himself short, avoiding revealing what specifically interested him. Franco's own sex education, he says, derived from his liberal upbringing, being raised in California in the 80s and 90s by "hippy parents". However, he admits that "there's definitely something in the air" in terms of how people think about sex today, even if a lot of it is happening on a tiny screen. "The internet has opened up communication," he says. "It's opened up access to a lot of things. We all know you can download Smurfs 2 as easily as you can download hardcore porn. You can have them both on your desktop in the same amount of time. So the boundaries between those things are, in some ways, kind of silly."

He reconsiders the word "silly". "We don't want to expose children to certain types of material, but if we're all adults and we all know we're watching pornography – at least a huge portion of the population is – then why are we prohibiting it from our narrative films?"

Although Franco occasionally riffs on modern cinema as if it's entirely bereft of boobs and balls – as if Behind The Candelabra and Blue Is The Warmest Colour haven't been among 2013's most acclaimed releases – he does make good points about Hollywood's inherent nervousness around homosexuality. Indeed, let's not forget that Steven Soderbergh's Liberace biopic was turned down by all Hollywood studios. For all of Interior. Leather Bar's film-school pretensions, it is a rarity to observe an actor of Franco's stature affiliating himself with such acts of same-sex intimacy. At one point in the film the camera fixes on Franco as he watches two men licking, sucking, slapping and kissing each other on a sofa, which seems like a pretty bold move for a man who was filming a Disney production at the same time. (It's worth noting here that Franco doesn't have sex in this film; in fact he rarely ever does onscreen, if you exclude Spring Breakers' mostly-snogging, pool-based threesome.) However, you get the impression that part of Franco's fascination with homosexuality might not all be just for the greater good of society; there's a part of him that might just enjoy the attention. The topless Seth Rogen smooch during his Kanye West parody Bound 3 being a good example.

'There's still some sort of Catholic prohibition of showing gay sex in explicit ways that straight sex can be shown in'

He wants to be clear, however, that this film isn't designed to shock. "There's still some sort of Catholic prohibition of showing gay sex in explicit ways that straight sex can be shown in," he says. "But there's two kinds of approaches to exposing gay lifestyles and gay sex to mainstream culture. There's the approach of like, 'OK, here it is in your face' – the extremes – and then there's, 'Hey, we're just like everyone, so it's not in your face, here's how we're the same.'" He pauses. "We're trying to take a soft approach and welcome people to this movie but also including some contact we know is what the audiences that will see the film won't see every day."

A few days before the interview Franco had uploaded a picture of himself kissing a man on Instagram, mocking gossip blogger Perez Hilton and other sites with the words "Just a Franco afternoon" scrawled across the images in Microsoft Paint. So I ask why he thinks that there's such an obsession with his or any male Hollywood star's sexuality.

"It makes a lot of sense to me," he says. "Celebrities the media love to track, they become surfaces or icons for people to project on to, or read into, and they are touchstones for the greater community to talk about, or help themselves understand who they are. They're reading into celebrities the same way they'll read into a book or a movie or a major event. It's a drag for celebrities, but they are cultural objects for mass consumption, so how we behave is very interesting to people. It's a big part of our lives. Sex and identity. And a celebrity's identity and sexual behaviour is very interesting for the same reasons."

As our interview comes to an end, it's time to release the star back into Hollywood, to a gay bar, to a library, to wherever the heck Franco wants to go, and I'm left pondering what exactly we are supposed to ascertain from stance on sexial behaviour. Despite his good looks, he does come across markedly un-sexual, especially for someone who routinely celebrates the sexual side of existence.

Perhaps a comment made by best friend Seth Rogen during Franco's Comedy Central Roast is the most accurate assertion of the star's current state of sexuality: "In this world, there can only be one James Franco, because if there were two James Francos, they would never stop butt-fucking each other."

Interior. Leather Bar is out on DVD from Monday