There's a large, pink billboard in London's Theatreland that heralds a phenomenon. And it's an unexpected phenomenon: A classic from the screen, from the 1980s -- the classic called "Dirty Dancing."
There were throngs of women, the odd dutiful boyfriend and husband, and bachelorette parties from as far away as Scotland the night we visited.
"We've seen the movie, we all love it," one gushing bride said.
"It's the hottest ticket in town," another shouted above the hullabaloo.
"People who come to see this are fans of the film," said Georgina Rich, who takes the leading role of Baby onstage. "So every line that is in the film is in the show."
There are even some scenes that were cut from the movie that have been restored to the stage show. The purists are pleased, even though there's no Jennifer Grey and no Patrick Swayze.
Swayze, who immortalized the role of dance god Johnny Castle, is in London, but he's strutting his stuff in "Guys and Dolls" just around the corner. In "Dirty Dancing," a guy named Joe Brown fills Swayze's celebrated undershirt.
"But he's not Patrick?" I asked some eager fans. "Patrick's too old and wrinkly now," came the disrespectful reply.
Emma Forbes is a British TV presenter and "Dirty Dancing" obsessive. She danced with Brown as research for an article she was writing about the show. A flimsy excuse to indulge a fantasy.
"You just want to take off your bra and knickers and throw them at him," Forbes said after seeing the show. "And I think some of the women actually did that."
Before "Dirty Dancing" even opened, it had taken in nearly $20 million in advance ticket sales. This is now being hailed as the fastest-selling musical in the history of London's Theatreland. Tickets, which regularly top at about $150, are changing hands on eBay for $350.
Why are those clutching tickets nearly all women? Well, read this line from the movie, uttered by an adoring Baby to a smouldering Johnny Castle: "I'm scared of walking out of this room and never feeling the rest of my whole life the way I feel when I'm with you."
Forbes explained the gender divide, saying, "It's the kind of guy line that men kind of go, 'Ooh, scary commitment, she loves me.' Whereas, us girls go, 'How great would it be to hear that?'"
Outside the theater, we thought we'd spotted two middle-aged men standing in line. But they were just dropping off their wives for the show. The men were going for a drink and some dinner.
"They like the dancing," one of them explained. "And they like the romance, which they don't get much of from us, let's be honest."
When the movie hit theaters back in 1987, it was a smash. A smash with a budget of just $6 million. Women who were teenagers at the time are now coming to see Baby come of age once again. According to Rich, the character is very easy to identify with.
"She's not perfect, she says stupid things, she makes a fool of herself in front of the guy she fancies," Rich said.
There's a scene in the movie where Baby first shows up at the Kellerman's staff dirty dancing bash, and "I carried a watermelon," is her first line to the über-cool Johnny.
"Ten years ago, there was the 100+ Club -- women that had seen it, in theaters, over a hundred times," Swayze said in a recent BBC interview. "That's the movie that sent my life and world into hyperspace."
The video was a multimillion seller, and now the DVD has spawned a new generation of fans, including millions here in Britain. The appeal of "Dirty Dancing" spans generations and continents.
"The key to 'Dirty Dancing' is its simplicity. Everybody has been there," Forbes said.
And the musical takes them back again, but in the flesh. When Forbes described the moment when Johnny comes back to take the last dance with Baby, she could barely contain her glee.
"He appeared right beside me," she screamed. "He walked right ... through the stalls being kind of mauled by women screaming."
Rich explained that from the stage she can then hear a collective intake of breath.
"They go really quiet before that line," she said.
When Johnny utters the immortal line, "Nobody puts Baby in the corner," well, the theater erupts. And this happens eight shows a week.
"It's a very important moment in theater," Rich deadpanned.
It's certainly a very lucrative moment in theater.
The "Dirty Dancing" musical began in Australia and arrived in London via New Zealand and Germany. The German translation of the big line is, rather strangely, "My baby belongs to me, is that understood?"
Next stop: Toronto. Then the United States. The show will hit various cities across the country and maybe even Broadway.