PART of Oxford city centre came to a standstill as a naked woman rode on horseback through the streets.
Last night's stunt marked the premiere of the film Lady Godiva - the debut by Oxford filmmaker Vicky Jewson.
There were wolf whistles and cheers from the crowd as the director's younger sister, Libby, 19, arrived on a white horse wearing nothing but a smile - and a sash and long wig to hide her modesty.
A crowd of hundreds swarmed towards her as she arrived.
Libby is one of the principal actors in the film - though not Lady Godiva, who is played by Holby City star Phoebe Thomas.
Libby said: "As I was leaving, somebody asked me: 'Can you get arrested for this?' "I said: 'It's a bit late now!' "It was very cold, but I was more than happy to do it for my sister. She's worked so hard to get everything together, I just want the film to be a success."
Although Miss Thomas was at the cinema, she chose to come fully clothed.
She said: "It was far too cold to come naked, but it's great to be back in Oxford.
"I had a fantastic time here in 2006 making the film. I've only seen parts of it, so it's fitting to be seeing the whole thing in the city where it was made."
A number of Miss Thomas's Holby City co-stars came out to join her for the premiere, along with Kara Tointon, who plays Dawn in EastEnders, and all stepped on to a pink carpet, which was rolled out into the street.
The organisers also used the opportunity to raise money for breast cancer charities.
Vicky Jewson, 22, raised almost £1.5m to fund the film - which is a modern day reworking of the legend of Lady Godiva, a noblewoman who rode naked through the streets of Coventry to protest against taxes.
The director, who has lived in Boars Hill, near Oxford, all her life, said it was fantastic to see so many people turn out on the night.
She said: "It's great to see it all coming together tonight. It was a bit nerve racking at times but the adrenaline got me through.
"We had considered Leicester Square for the premiere, but thought it would be fantastic to do it here in Oxford - it's a fantastic thing for the city.
"The story has never really been told before, so there was no pressure to do anything new with it.
"It's just a story about a young woman doing something inspirational for a worthwhile cause."
The young director was also quick to thank her little sister for agreeing to arrive at the premiere naked.
She said: "We were having problems trying to find someone to do it, and Libby just said: 'I'll do it.' She was fantastic."
Lady Godiva will go on general release on Friday.