Whether it’s because of love for the lady herself or recollected joy in the TV sketches Victoria Wood wrote for her, Julie Walters had only to jerk and teeter on stage for the folks near me to dissolve in uproar.

I laughed a bit too, because she’s pretty funny when she’s wearing the old overall that gives her character its name, yellow rubber gloves are stuck in her belt, her mouth is set in a batty rictus, her back is arched to resemble London’s congestion charge symbol, and you can’t tell where her hairnet ends and her hair begins. But is her Mrs Overall as hilarious as all that? Indeed, is the musical play Wood has derived from her spoof of an antique-shop soap opera as funny as some of us hoped? Well, all right, sometimes so.

Certainly, Trevor Nunn’s jaunty production teems with lines that few but its author could have penned. Her name may be Wood, but her writing is concrete. A man doesn’t just say “I’ll deal with this”; he says “I’ll handle this, I have a scrotum”. A woman doesn’t ask “how’s your poor sick mother?”; she asks “is she still in an attention-seeking, near-death coma?” .

Since I enjoy such stuff, it seems ungracious to complain that the evening isn’t notable for narrative clarity or that the story seems an excuse for concrete Woodisms.

The first act introduces us to several of her pet performers, among them a haughty, tweedy Celia Imrie, an off-with-the- pixies Duncan Preston and, of course, Walters herself. They play professional actors who have joined members of the Sutton Coldfield Light Operatic Society in the Enoch Powell Arts Centre to stage an Acorn Antiques musical.

The target here is luvviedom, as represented mainly by Neil Morrissey as the pretentious director who is turning the show into something “incredibly subversive”. But when Walters wins the National Lottery she sacks him and takes the revised musical to London, giving us a second act complete with lunatic plot twists, parodies of Sondheim and Lloyd-Webber, Morrissey as a loan shark and Josie Lawrence as the business heavy who plots to turn Acorn Antiques itself into a slick coffee shop: “We’re second, so we grind harder.”

Yes, the lines keep coming, though those within the songs tend to be masked by the music, which is a pity, for Wood is as sprightly a lyricist as she is a dramatist, composer and everything else.

The result is mischievous, good-natured, charming. But a comic masterpiece? Not really.

Until March 19.

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