Though it offered the filthy pleasure of Stephanie Beacham pouting her lips and purring 'a demain' at Dervla Kirwan in one of the most excruciating flirtation scenes ever committed to film - a car crash of a lipstick lesbian encounter that made you want to flick over but somehow you couldn't - the finale of Material Girl (BBC1) was a distinctly bargainbasement affair. And the BBC knew it, tugging it out of its usual Thursday night slot and shifting it to after the news on Wednesday. Not exactly a show of faith. For some reason, Material Girl ditched the fashion satire it kicked off with and opted instead for a second-hand chicklit love-triangle story that never felt remotely convincing. It was so last season even before the credits rolled.

After an impressive start - or maybe I was just swayed by the fabulous shoes - this series has gone the way of its sister show Hotel Babylon and now proudly sits on a shelf in between that and Footballers' Wives.

You know you shouldn't be watching these programmes and that they'll only rot your brain, but there's something quite addictive about them. Again, maybe it's the shoes...

Tonight Ali is putting the finishing touches to her first ever collection and utters the deadly line, "I think I'm almost there." She might as well say, "Right, time for something to come along and mess up all our hard work so badly we have to start again and come up with a new collection in less than a week."

It's a scenario that's happened a million times before and you always know the outcome. Still, this one has off-shoots that involve lots of toned men in their pants and Mimi finally getting to stick two fingers up at her bitchy colleagues.

My new guilty pleasure did little to make me feel any better about it. Actually, if they don't find a new plot line for next week I may have to tune out: how many times can we watch Ali from Material Girl come perilously close to reputational and financial ruin, thanks to the evil plottings of fashion nemesis Davina, only to pull one out of the (designer) bag at the final minute, leaving egg on her rival's face and stealing the spotlight? The edge of my seat is looking increasingly distant. In brief: this week, Ali's supermodel BFF, Lydia, almost wrecked her career by throwing up on herself after a party. Meanwhile, Davina had bought up all the red fabric in London, forcing Ali and Marco to buy in bulk. In order to compensate for the volumes ordered, Marco went behind Ali's back and hired sweatshop labourers to make the dresses, including one to be worn by Lydia at her ball in aid of a human rights charity, the very event that's supposed to act as her PR relaunch. Doh! Needless to say, Ali saved the day in the end, thanks to her unique combination of compassion, talent and heady good looks. Who would've thought, eh?

OK, OK, I admit it, I didn't just "happen to accidentally" catch Material Girl again last night. I went out of my way to watch it, crap script, corny premise, awful costumes and all. Honestly, it wasn't much better than last week: it's still budget as anything, and chock-a-bloc with cringey clichés. But it certainly wasn't any worse. And at least Ali's wet boyfriend didn't feature too heavily. This week was dominated by the evil Davina and her plans to sue our heroine. The drama! Perhaps - just perhaps - this is to become my (very) guilty pleasure of 2010.

Material Girl, billed as a "comedy drama", has at least a certain perkiness about it, as it unwinds a tale about Ali, a talented young designer who leaves the salon of high-bitch Davina to set up on her own with somewhat-shady Marco as her business partner. The deep structure of this shallow piece is that Ali's ambition is counterpointed by her lovely nature. Although her best friend warns her that "you can't heal everything with fashion", that's really what she does, putting a talented writer, whose autobiography has been gutted by its film version, into a dress much more glamorous than that worn by the self-obsessed star at the premiere. Along the way, a lot of bitchery, both gay and straight; some very soppy romance; a deal of catwalking; flurries of flouncing. Not funny but easy on the eye.

Ostensibly a comedy-drama, but much nearer in spirit and dramatic depth to pantomime, Material Girl stars Lenora Crichlow as Ali - unsung, unappreciated and cruelly exploited as chief designer of fashion house diva Davina Bailey. Forced to stand in the wings, while wicked boss Davina garners all the catwalk kudos in Paris, Ali is then passed over for the promotion she is entitled to and resigns in protest. But fashion can be a cruel, cruel world to a poor, defenceless girl with just a design portfolio and a pair of Manolo Blahnik's to fall back on...

The stage is set for a reworking of Cinderella with no less than two handsome princes, a disreputable old count, several best friend Buttons and more queens - wicked or otherwise - that you could shake a wand at. Its all very frothy, shallow and silly, but Material Girl is spuriously glamorous and provides enough undemanding fun to fill an hour. Whether it can sustain a series remains to be seen.

I'm guessing there'll be some crossover appeal between Glee and Material Girl, BBC1's new early-evening drama set in the preposterous world of fashion. Lenora Crichlow as hot young frock designer Ali looked more like someone who might work at Next, but perhaps she's meant to represent wholesome values amid the preening, cut-throat, candyfloss-haired twits she's up against.

If Glee grabs its stereotypes and gives them a big, bone-crushing bear hug, Material Girl, the BBC's new fashion-world drama, lacks the courage even to shake hands with the stock characters it promised to deal with.

The first episode found young designer Ali putting the finishing touches to what was supposed to be a fabulous high-end collection backstage at a Paris fashion show. Sadly, it looked more like the latest Ann Summers range had exploded all over the catwalk and the credibility of the show spiralled downwards from there on.

The problem with the costumes (The Apprentice has better-dressed casts) is one of many. Worse is the uneven tone - Dervla Kirwan, who went high camp with her arch bitch performance, clearly didn't get the memo that told the rest of the cast they should play it straight to the point where they seemed to be boring themselves.

The whole thing is accessorised with some crudely sketched moral dilemmas ("Is fashion more important than being a good person?"), lots of clunky name-dropping and a female Iraq veteran with Hollyoaks body whose post-traumatic stress appeared to be solved by a skimpy orange dress.

The fashion industry may be many things, lots of them worthy of a send-up, but it is rarely dull and never worthy so it's baffling that Material Girl managed to be both. An independent report published earlier this week suggests that the Beeb should spend less time and money chasing 16- to 35-year-olds and focus on quality broadcasting. If confirmation were needed, this series is it.

Right, that's the froth dealt with. Now to the espresso underneath. With a glass of Veuve Clicquot and a line of coke on the side. Because Material Girl (BBC1), an important new drama set in the world of fashion, takes on the ­altogether more profound question: what to wear? OK, it's silly and deeply shallow. It's also gorgeous, fizzy, bitchy, self-indulgent, obviously bad for you but dangerously addictive. Careful, Material Girl could become a habit.

Dervla Kirwan makes a splendid queen bitch evil designer with no talent but an impressive Rolodex. Being ­Human's lovely Lenora Crichlow is again lovely as Ali, the talented young designer, who's tottering in five-inch heels along the thin line between the real world and fashion nonsense. Only the hunk is wrong - too puppyish and doey-eyed to be a hunk, I think. And since when did motorcycle couriers ride Harley-Davidsons?

It's part of the Babylon franchise, based on the writing of Imogen ­Edwards-Jones. This is better than ­Hotel Babylon though - simply more fun. As usual, IE-J wrote her book with "Anonymous", an insider from the world in which it's set. Unfortunately, although I understand chaos theory perfectly, I know very little about ­fashion, so can't ­comment on its veracity. But I know a woman who understands fashion well, my own insider - let's just call her Guardian fashion editor Jess Cartner-Morley.

The daft, post-show, backstage ­"Darling, you are a fashion goddess" conversations between the celebrity and the designer are spot on, says JC-M. Plus the brash, very London supermodel, and the slimy Eurotrash ­business partner in the turtle neck - right again, those people are real.

Obviously a lot of old fashion cliches are dragged out, some of which JC-M could have done without, such as the scene in the shoe shop where Ali sells her soul for a nice pair of shoes: Jess is so over that scene, she's seen it about 5,000 times, come aaaawn. And where it's just plain wrong, she says, is when the baddie journalist demands sexual favours of a GIRL - very unlikely. The men in fashion really are gay. Oh, and she likes it. So I was right about that.

Flights of fancy were evident in the glossy BBC drama Material Girl, an hour that felt a bit like a day of blistering sunshine and horrendous hailstorm: funny then not funny; sharp, then suddenly, lamentably pedestrian. The story of a plucky young fashion designer and her evil former boss had all the Cinderella elements of Ugly Betty, the show it most obviously resembled. However, whereas the latter glorifies in its absurdity, its camp cartoonishness, Material Girl allowed Dervla Kirwan as Davina to dress up as Cruella de Vil, and snarl and scowl icily, but then the tone receded and became all workmanlike and clunky. British, in other words.

Lenora Crichlow as Ali, who had left the evil Davina to set up on her own, slugged beer from a bottle (to show she was a regular gal), she didn't want some fancy-schmancy star to wear her dress to the Baftas (yeah right!). Her boyfriend is just a regular guy courier who rides a motorbike and who puts her, chaste and untouched, to bed after she gets hideously drunk. What a prince.

Material Girl isn't as bad as some critics say, but it's not as fun as it could be. It's not really new to identify fashion as vapid and fashion people as empty, self-serving egotists. (Oh and for all the men to be bitchy, camp gays: there are not enough of them on TV, thanks!) There's a great moment in The Devil Wears Prada where Meryl Streep tells Anne Hathaway she can pretend to be all superior about this empty world, but what about the blue jumper she's wearing ... which Streep then deconstructs piercingly. Material Girl could be very funny, if it had a sharper, more knowing respect for the world it sets out to satirise.