I’m going to come clean. I was a Sex and the City fan. Like so many other women I had a grudging respect for a woman who could wear a Hallowe’en pumpkin for a skirt and shoes that looked like attenuated pigs’ trotters and still take herself seriously. I am the target audience for the long-gestating film follow-up to the series that charmed us all with its frank-talking, froth and fabulously silly clothes.

So does Sex and the City retain its pert charm on the big screen, five years on? Well, as Samantha might drawl with a suggestive pout and her talons sunk into the flesh of her latest boy toy, like so many things in life it’s all a question of timing. And the timing here is a little off, not least because the length – 2½ hours, near enough – seems like an awful long time to spend with these irritating, self-obsessed women, however much we may have missed them.

There’s also something that suddenly feels a little jarring about the mantra of having it all – or at least as much of it as you can charge to your credit card. When, for example, Samantha can’t “get off”, she “gets things” – cue a shot of Samantha smirking in front of a freight container of Gucci carrier bags.

It’s perhaps unfair to suggest that the writer (Michael Patrick King, who also directs) should have had the foresight to predict the almighty downer that is the credit crunch, but suddenly it’s a lot harder to care about a bunch of women who swap real estate like top trump cards and who can, without a flicker of guilt, blow more than $600 on a pair of nasty, tacky shoes.

And then there’s the obsession with labels and price tags, which suddenly seems kind of gauche rather than excitingly frivolous and decadent like it used to be. “That cushion cost $300!” says Carrie as Samantha’s canine alter-ego frantically tries to mate with it. I like buying cool stuff as much as the next shallow, rapaciously consumerist person who grew up in the Thatcher era, but still. When one character buys an outfit that isn’t a designer label, it’s a really big deal that becomes a plot point.

All this wouldn’t be so much of a problem if the film delivered the requisite amount of sass, attitude and, crucially, laughs that we have come to expect from the show and its wisecracking coven of fashion mavens. Now that the girls are in their forties – or in the case of the remarkably well-preserved Samantha, turning 50 – the single life that they once celebrated is starting to look a little more like a life sentence.

Critics have been asked not to give away crucial plot points, but I will say that when one of the key characters’ relationship breaks down, she’s bed-bound for two whole days. It’s as if, just as the skin loses its elasticity as we get older, so the heart loses its ability to bounce back. Which is exactly the kind of bleak and depressing reality that we need the old SATC formula of escapism to blot out.

There are a few very funny moments. A throwaway Diane Arbus gag from Carrie’s editor at Vogueis priceless. A sequence involving Samantha and some homemade sushi makes you realise how much you were hoping for more of the old-style SATC naughtiness. Charlotte’s big embarrassing incident is a moment of scatological inspiration. And a new addition to the cast, Jennifer Hudson, as Carrie’s assistant, is a likeable, funny presence.

But for the most part, the tone is downbeat. Carrie’s endearingly dreadful puns now seem hollow and forced. It’s like being reunited with old friends only to realise that you’ve grown irreparably apart.

15, 145mins

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