If Stephen Schwartz’s 1972 musical were to be revived on the scale of his mega musical Wicked, I’m not sure I could get very excited about the prospect.

His groovy score serves the cautionary tale well but is hardly inspirational. More problematic is that the eponymous central character — son of mediaeval conqueror Charlemagne — is an angsty princeling with an empire-sized sense of entitlement who mopes around his mass murdering dad’s kingdom looking for something to do. It is very difficult to care about his fate.

Yet this pared down revival in the back yard of a bar in London’s Vauxhall has such charm, commitment and energy, you care instead about the fate of the production.

This is not least because of the hoops any show has to go through to keep to Covid guidelines. And since the latest rules were announced, the show’s times will have to accommodate the bar’s closure at 10pm — not easy as the cast are performing two one-and-a-half-hour shows per evening.

You might think you have entered a revival of Hair. The mood is hippyish and has more than a whiff of flower power about it. Meanwhile, as Ryan Anderson’s Levis-wearing Pippin scribbles into his notebook, his five fellow cast members multi-task as his chorus, conscience and narrator, played by the excellent Tsemaye Bob-Egbe.

This is the first time Schwartz has consented to the show being performed with such a small cast and director Steven Dexter repays the trust with a production that is as well drilled as it is necessarily compact. Thanks to Nick Winston’s choreography the dancing uses every inch of courtyard space but without feeling cramped.

Yet it is the cast’s commitment that keeps you hooked through Pippin’s self-indulgent odyssey. As his mother, Joanne Clifton injects glamorous teeth-and-smiles glitz into the role, lending the evening a pungent satirical air, while Dan Krikler as the mad dad squeezes laughs out of a thinly drawn tyrant. Tanisha-Mae Brown also deserves a mention as Catherine, a widowed single mother who does more than anyone to make Pippin a decent human being.

All this is more than enough to keep the socially distanced, mask-wearing audience engaged until the plot reaches its pleasingly unsentimental climax.

The result works so well at this small scale it must be hoped that that show is allowed to extend, though perhaps not to the bigger venue that it is tempting to think it deserves.