The four friends are squealing with excitement. “OMG! OMG!” they say over and over with wide-eyed glee, their flip-flopped feet performing an involuntary jig. One of them has just managed to get Kim Cattrall’s autograph, despite the protestations of a burly security guard. Her blonde friend proudly shows off a clear snap of a smiling Sarah Jessica Parker on her camera phone. “If I said SJP, would you know who I mean?” hollers another into her mobile, while the fourth member of the gang frantically updates her Twitter.

These women are indulging in New York’s latest spectator sport — watching the filming of the new Sex and the City movie, live on the streets of Manhattan. Because so much of the movie’s action takes place downtown, not in the studio, fans can indulge in a unique experience. They follow the making of the movie in real time, updated daily, just like a new episode of their favourite show, with fresh locations, plot twists and outfits.

When the first SATC movie came out, critics wondered whether it could ever replicate the success of the hit HBO series. It did, thanks to the passion of die-hard fans. Now the same SATC addicts are showing their dedication; first they find out, via Twitter, where the new movie is filming, then they descend daily on the location to catch a glimpse of their favourite stars, check out the outfits and maybe snatch an autograph.

The excitement on the ground is palpable, but the hysteria has spread beyond street level. You don’t have to be in New York to experience it. Simply log on to one of the constantly updated websites that detail each on-set development. Everything has been reported, analysed and picked over, from the 1980s flashback sequences to the accidental plot revelations about Carrie and Big’s split, rumours of a rift between SJP and Cynthia Nixon and speculation about SJP’s facial mole. (For continuity purposes, make-up artists have, apparently, made a fake one after the actress reportedly had hers surgically removed last year.) So much has been seen and talked about that, by the time the movie comes out next year, it will be as familiar as one of the many reruns of the show.

The day I went along (following a tip on Twitter), the streets near the set, in SoHo, were lined with location vans and the stars’ trailers. The crowd — about 150 strong — had congregated on either side of a building on West Broadway, where SJP and the gang were inside filming a restaurant scene. Women of all nationalities and ages, from teens to fiftysomethings, clutched camera phones and celebrity magazines. Some had brought reluctant boyfriends or husbands, but most, like the cinema crowds who flocked to see SATC the first time round, were groups of girlfriends who had come along to share the experience. Many stayed for hours. Four pretty twentysomething blondes, sporting Carrie tribute ringlets, skinny jeans and pretty printed tops, were staking out SJP’s trailer, armed with takeaway salad for sustenance. They confessed to being huge fans and had already been on organised SATC location bus tours (demand for which has shot up 30% since filming began). Security guards kept people back from the cameras, but there were no barriers. One couple made a break for fame and ran across the set in an effort to be in the movie, but everyone else stood by patiently, bantering with the bouncers and swapping SATC stories to pass the time.

Then came the moment they had been waiting for. The SATC stars finished filming and began to make their way back through the crowds to their trailers. “OMG! They’re coming towards us,” cried one woman, suddenly horrified that the big event was actually happening, and scrambling for her pen and camera phone.

One by one, the stars filed past. There was no sign of Kristin Davis, but Cynthia Nixon swept by in a printed dress and studded sandals. Kim Cattrall passed through the crowds reaching out to shake hands and sign autographs. “She looks much thinner in real life than on TV,” commented a redheaded fan from Florida. But the warmest reception was given to SJP, wearing rolled-up high-waisted jeans, a checked shirt tied under her bust, 1980s-style, and studded suede stilettos. Everybody cheered, clapped, shouted “Hi” and greeted her with a chorus of compliments: “You look great, Sarah!” Some women were visibly moved by the sight of her. SJP, in turn, shouted a big, friendly “Hi” back to the crowd, and stopped to sign autographs and meet fans.

It was a scene of great affection, mutual goodwill and real emotion. The women who had waited with their friends all day to get close to the stars were so delighted to see SJP and the gang back at work, and looking so pretty, they glowed with pleasure afterwards. That the actresses were keen to reach out to them says something, too. In this happy interaction between fan and idol lies the essence of SATC’s appeal. It has harnessed a rich and powerful emotion, which has its basis in female friendship and the idea of women supporting each other. The new movie looks set to do the same. That day, in a small corner of downtown Manhattan, you could really feel the love.

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