You’d really need to be Prince Charles to get the most out of this curio: or at least a septuagenarian devotee of the Goons and inveterate nostalgist for the era when BBC radio announcers wore dinner jackets. In case you don’t even know what the Goons were, they were the forerunners of every manic comedy programme since, from Monty Python to League of Gentlemen to Little Britain, pioneers who established that surreal and illogical sketches and oft-repeated catchphrases could make the kind of radio and later television people talked about at work the next day.

The Goon Show deployed the talents of a trio of ex-forces comics who didn’t fit so easily into the post-war entertainment circuits of variety and working men’s clubs: oddball intellectual Spike Milligan, silly-voiced Welsh dirigible Harry Secombe, and surface-suave but probably pervy Peter Sellers.

Scripts were peppered with a variety of sound effects and odd noises, one of which, a ‘raspberry’ signalled the moment Secombe, who couldn’t play a whole scene without dissolving into ribald laughter, was about to lose it. Milligan tailored this into a faux-Victorian melodrama about a Jack the Ripper figure who stalked London society – The Phantom Raspberry Blower of Old London Town.   Post-Goons, Milligan worked with Ronnie Barker to produce a 1971 television version of the same nonsense with the lush production values of Sherlock and in which a then-unknown David Jason provided the sound-effect raspberries. So it might be tripe, but at least it’s pedigree tripe.

Jobbing actor Lee Moone has taken up the sticky baton of Milligan and Barker and refreshed the scripts into a staged radio play format complete with vintage BBC microphones, dinner-jacketed announcer James Petherick and Jessica Bowles’s superb one-woman orchestra of sound effects which are the highlight of the evening.

They need to be, because the acting is indulgent at best, and occasionally under-rehearsed: aping the ability of the Goons to corpse at their own witticisms is one thing, but frequent stumbling over words in a script you’re only reading aloud is shoddy.

The troupe fare better when they break into song, with neat harmonies and Matthew Freeman’s distinguished pianoforte. Best is the cheeky first-act closer featuring a great succession of you-can-see-it-coming-but-laugh-anyway double-entendres to make the naughtiest schoolboy snigger.

The show lacks pace in the second half but as well as some audience participation there’s a ‘celebrity’ Phantom, on Saturday and in a neat link back to original Raspberry blower David Jason, a splendid turn from John Challis who played Boycie in Only Fools and Horses.

With polish, and perhaps some sharpened cut-glass accents, it’s guaranteed a life beyond the three-night run at the St James’s and sure to amuse mature audiences across the provinces for years.