Tell Me On a Sunday, Gielgud Theatre, London

"I always get the short end of the stick," laments Denise Van Outen in this one-woman show about a lass from Ilford looking for love in New York. She then sings "I think I feel sick", but anyone observing her character's behaviour, as well as her flouting of logic and idiom, might well comment, "Could it be, dear, that you're selfish and thick?"

The 75-minute Tell Me on a Sunday has been revised by lyricist Don Black and Andrew Lloyd Webber, who has contributed, he says, "five completely new songs". Well, that would be a first. But the effect of the changes, besides a bit of "updating" (our heroine has a laptop) is to push the show further up the estuary. "I've me' a bloke," Ilford Girl (as we must call her, for she has no name), announces, and bids a friend goodbye with the affectionate epithet "dozy tart". Indeed, this is a show for those who are happy to be so addressed, and men to whom it represents their ideal woman.

In a role that might be an audition to fill the place left vacant by Saint Diana of the Dumped, IG flees the end of an affair in Essex only to hook up with one bastard after another. A Hollywood agent ("Tyler King calls all the shots!/ Tyler King gives me the hots!") dazzles her briefly (spotlights shine into the audience to replicate this effect), then won't take her calls. IG sings a mournful accusation ("You Made Me Think You Were in Love"), despite having shown us only her desire to marry money and meet the famous. A young photographer romances then drops her, but two seconds later a voice on her answering-machine asks her out: "It would be great to see you." "He seems such a nice man," IG says brightly, grasping at straws like they're going out of style. Mr Nice, however, is married, and reneges on his promise to leave his wife, but not before introducing his nine-year-old daughter to IG.

Crassness and sentimentality are familiar bedfellows in this show, but never more so than in this scene, when IG capers like a much younger child, sings "I'm very you, you're very me", and tells the little girl that she will be her "second mother" and "spoil" her. What Tell Me on a Sunday needs at this point, one feels, is for Dawn French, playing a rejected divorcée just a few yards down Shaftesbury Avenue, to appear and blast this appalling twit off the stage with "Are you out of your mind?"

When not absurdly pompous (the grandiose sound during the emotionally low-key opening scene would do for the coronation of an empress), Lloyd Webber's music is laughably trite: IG, down in the dumps, walks in place, head lowered, as horns and sirens play their part in "Symphony of the Heartless City".

Van Outen seems a nice girl, but her singing and acting are very average, and I don't even mean "average professional". Her voice is often harshly nasal, and, when she turns up the volume (sometimes, oddly, in the middle of a word), she produces an unpleasant and at times unintelligible noise.

"Additional material" was provided by Jackie Clune, but apart from her and Van Outen, those involved in the show (Matthew Warchus asked to direct – why?) are men. If there's such a thing as a low-brow existential question, it could be asking whether this show or French's (directed, written, and enacted by females) shows more contempt for women.

To 26 July (020-7494 5065)