Scarlett Thomas: Oh, Carrie. It was more than a one-night stand, but I am so over you

Four single women, one big city and many, many guys. Yes, the "revolutionary" American television show Sex and the City has just started its fifth season in the UK, with the kind of fanfare that TV companies use to denote A Big Event: a whole evening devoted to the show, complete with documentaries and repeats. The latest series follows the usual format. Women saying "fuck" – and a lot worse – and having casual sex while, yes, looking for Mr Right. People still find it shocking, despite it being the same comfortable old girly story with which we are all familiar. You know, the one about four best friends who are always there for each other, who never feel lonely (and who seem to eat all the time and never get fat). In a world in which all women are thin and white and have personalities signified by hair colour, this story has Samantha, the blonde, vivacious one; Charlotte, the shy, romantic brunette; Miranda, the red-headed high-achiever; and Carrie, the curly-haired, chaotic one. Take away the alcohol and the anal sex and it could have been written by Enid Blyton.

In a Time magazine poll in 2000, 54 per cent of women said that they felt it represented a "realistic portrayal" of single life. Logic would suggest, however, that if everyone is in one of two possible states, "single" or "married", and if male American TV producers are able to fully examine these states, then it is unclear why novelists, artists, scientists and philosophers bother to try to examine life at all. TV can be comforting, stupid or fun, but it isn't ever realistic. All TV offers us is the comfort of structure – the interesting bits of life made into nice stories with impossible, but satisfying, resolutions. But Sex and the City doesn't even manage that, in the end.

I'll admit it. When I first watched the programme, I did rather like it. I liked the title sequence, which features an odd-looking woman with bad skin, wearing a white tutu and skin-tight pink leotard, getting splashed by a vehicle as she walks through New York. She turned out to be the lead character, Carrie, a shoe-loving journalist who seems able to work only in five-minute bursts, in bare feet and while wearing designer leggings and small T-shirts. Who would have anticipated the axis of evil spawned by Carrie's cringe-making, one-theme-per-episode journalism? In the past four years, her insipid style ("Why Won't He Commit?" etc) has continued to infiltrate newspapers, and many of them churn out lifestyle features and relationship analysis in epic quantities. And then there's all the fashion journalism that's simply about Sarah Jessica Parker, who plays Carrie. Yes, the woman with the tutu has become a fashion icon. (It would seem that I misread the title sequence all along. Being thin means it doesn't matter that the designer clothes you are wearing look bizarre. Perhaps if I hadn't moved from London to Devon I would realise this. Around here no one is thin and everyone wears varying degrees of fancy dress, but I digress.)

Sex and the City progressed from focusing on Carrie and her friends' one-night stands to relationships that lasted longer than one episode, which was satisfying for a while. But, just as a shop will never sell you the ultimate product that will stop you buying anything else, a television show about searching for relationships can never give those relationships to its characters. So, as the characters got older, their relationships broke down and Samantha completed the transformation from promiscuous vamp to unwatchable pantomime dame (Sex and the City doesn't do character depth or development, each archetype simply intensifies), this fun, promising drama became depressing. These poor characters were stuck, like nailed-down butterflies. At least conventional romantic narratives eventually end.

At times it seemed the relationship between the women and the city (rather than the sex) would develop. But yet when I think about this now I can only see Carrie, having been mugged of her Manolo Blahniks, shouting "Somebody stop him, he stole my strappy sandals!". In this world, the city is nothing other than a place of consumption: shopping and fucking. Ultimately, Sex and the City seems to have one message: "Do you feel degraded after your latest tragic one-night stand? Go and buy some more shoes, then." Maybe celibacy – or a trip to the suburbs – would work better.