Nostalgia is not what it was. This is a jocular aside made in this affectionate recreation of a long-lost Kenneth Williams radio series and it acts as a critique of the stage production too. The team that had a shamelessly backwards-looking hit with Round The Horne...Revisited is trying to pull off the same trick here but the results are a little less magical.

There are certainly laughs to be had thanks to plenty of old one-liners by Brian Cooke and the late Johnnie Mortimer, yet there is not the same misty-eyed frisson. Perhaps because this vehicle for Williams is not held in quite the same esteem as Round The Horne. Nor are there the same memorable characters. Gay bantering twosome Julian and Sandy no longer dominate, Rambling Syd Rumpo is gone.

It is a pity, because Robin Sebastian is never less than brilliant as Williams. Not quite as acidic as the original but he can certainly deliver a nostril-flared line. “Infamy, infamy, they’ve all got it in for me”, swiped from Carry On Cleo, gets two huge laughs. Elsewhere however, the script feels thin, trading on wince-inducing puns, particularly in an overlong Gone With The Wind spoof, Back With The Bicarbonate.

The supporting cast offer good value as they potter around the on‑stage radio studio. Charles Armstrong plays a straight bat as suave announcer Douglas Smith. Jeremy Paxman lookalike Nigel Harrison is a persuasive Hugh Paddick. Only petite Emma Atkins strikes the wrong chord. She plays Carry On stalwart Joan Sims, though could more easily pass for Barbara Windsor.

Director Michael Kingsbury keeps things simple, maybe too simple. This show is effectively two radio broadcasts and little else. What this is crying out for is some back story. Kenneth Williams had a fascinatingly tortured psyche, as anyone who saw Michael Sheen tackle him in the BBC drama Fantabulosa will know. Stop Messing About reminds us how funny Williams was. It would be nice if it also hinted at what made him tick.

Until 24 May (not tonight. 0844 847 2475, www.stopmessingabout.com).