It’s been over 30 years, and some people still have not recovered. The crossing (or, technically, uncrossing) of legs that shook the world has not aged at all. Murder suspect Catherine Trammell (played by a 34-year-old Sharon Stone) undergoes an interrogation, but it is she who ends up tormenting the police. The mouse and the cat have never been so in heat. Catherine is the only one who enjoys the situation.

Oh, and millions of spectators. Basic Instinct (directed by Paul Verhoeven, 1992) was the fourth-highest grossing film of the year. Sex (and the desire of it) corrupts every shot until it almost melts the celluloid of a movie that became an instant classic. And all because many teenagers (and some grown men) burned the video by repeatedly rewinding and pausing the scene in question.

Today, a mystery – more juicy, though less deadly – remains unresolved. Did the director have the consent of the actress to portray her crotch for posterity?

Sharon Stone, basic instinct

The detective with an addiction to risk (and everything else), Nick Curran (played by Michael Douglas), knows that Trammell is not wearing underwear. He spied on her while she was dressing in the previous scene and has found that for her, lingerie is unnecessary. The viewer also knows it, and so witnesses that interrogation with an open mouth. Will Trammell dare to uncross those legs, to daze the males of the pack? Of course, the answer is yes. She has not gotten there by being shy.

There are two versions of how the famous scene happened. According to the director of the film, Paul Verhoeven, Stone knew perfectly well what she was doing and was delighted with the perverse situation. According to the actress, the director exploited her. “When we shot it, it was going to be a hint,” says Stone, “but [Verhoeven] told me: ‘You can see the white of your underwear, I need you to take it off.’ He assured me that nothing would be seen. So I took off my underwear and put it in my shirt pocket.”

So far, both versions of the story coincide. The conflict arises when, at the end of the shoot, the director and the actress analysed the scene in question. “At that time, there was no high definition”, continues the actress, “so when I looked at the monitor, I really did not see anything.” Everything changed when Stone, the crew, and the whole world saw the film on a giant movie screen.

“I was in a state of shock,” says Stone. “At the end of the movie, I got up, walked over to Paul Verhoeven and slapped him.” The actress recognises that the shot is appropriate for the film and for the character, and that if she had been the director she would have kept it in the final cut. “But I would have had the courtesy to show it to the actress,” she concludes.

Someone is not telling the truth. According to Verhoeven, it is not him. “Sharon is lying,” he tells ICON. “Any actress knows what she’s going to see if you ask her to take off her underwear and point there with the camera.” He claims that when Stone saw the result of the scene on the monitor, she did not have any reaction. “I think it had to do with the director of photography [Jan De Bont, who would later direct Speed and Twister] and I am Dutch, so we act with total normality towards nudity. And Sharon was carried away by this relaxed attitude. But when she saw the scene surrounded by other [American] people, including her agent and her publicist, she went crazy. Everyone told her that this scene would ruin her career, so Sharon came and asked me to take it away. I told her no. ‘You accepted, and I showed you the result,’ I said, and she replied, ‘Fuck you.’ But Sharon is not going to tell you that, surely not.”

The legend that surrounds the filming of Basic Instinct would give enough material for another thriller, and with plenty of erotic scenes as well. Screenwriter Joe Eszterhas claimed that he slept with Stone to celebrate the success of the film. Meanwhile, several LGBT associations attempted to boycott the film because of its negative portrayal of bisexual women. And for months, Michael Douglas referred to Stone as “a second-rate actress”.

But the director always believed in her. When A-list actresses (Julia Roberts and Michelle Pfeiffer) read the script, they asked if he would shoot the scenes of sex and violence as they were described in the text. “No,” responded Verhoeven, “they will be even stronger”. Stone did not have those inhibitions. She had just posed nude for Playboy in an attempt to revive her career. And what if he reactivated it? A quarter of a century later, Basic Instinct is still the only movie that makes you want to smoke a cigar when it’s over.

Eszterhas, who did not write the interrogation scene because it was Verhoeven’s idea, resents this legacy. “When you have [on your CV] one of the most famous erotic scenes in the world of cinema, it eclipses the film, which is a tense and psychological modern black film,” he laments. The sequence was the focus of clandestine hangouts when parents were away from home and also of parodies. In one of the most recent of them, comedian James Corden tries to seduce an older Michael Douglas, achieving an effect different from that of Catherine Trammell.

There remains an open mystery – perhaps the most complex of all. Who is Sharon Stone? A sexual predator ready for anything, or a naive victim? Probably both, and neither, at the same time. Stone made Trammell a legend – giving  her a face, body and pubis – but ended up condemning her.

Rita Hayworth lamented that men went to bed with Gilda (her most iconic character), but woke up with her. Stone suffers a similar fate. She is remembered in film history, but only as Catherine Trammell. A cornered woman, she made fashionable the perverse female characters who do not apologise for enjoying sex. Demi Moore made this the basis of her career. In the crazy 1990s, the cultural revolution was without underwear, and Sharon Stone had the audacity to be the first to take it off.

“Nobody else could have done that job,” says Verhoeven. He adds: “She can be very cruel and very charming, and she is able to change the look from one state to another in a second.” Sharon Stone is like that – she is Catherine Trammell, but without the ice pick.

Everything indicates that this mystery, which is now part of popular culture, will never be solved. In that room were only Stone, Verhoeven and De Bont, because the actress had asked to shoot at the end of the day and with no one else present. The resulting scene soon became the official erotic moment of the 1990s.