In 1960’s Saint-Tropez, a self-described gigolo who yearns to be a movie star meets a brassy American woman with a shady past. Together, they plan the heist of the century: the theft of the world’s second-largest diamond from under the very noses of the Riviera elite. But Georges the gigolo isn’t very good at this, while Frankie the burglar prefers to work alone. The scene’s set for a zany multi-character comedy, where all the roles are performed by last year’s Buxton comedy award-winners, Nathan & Ida.

The decadent milieu is neatly captured in a toe-curling retro TV parody, where an oily host dances and smirks his way through an outline of the back-story. From there, the character changes come quick and fast, as the two performers pull ever more props out of a matching pair of suitcases. There are gendarmes’ hats with matching comedy moustaches; there’s a cane that doubles as a motorbike’s handlebars, and of course there’s the enormous diamond itself. The characters are pleasantly ridiculous but the plot makes perfect sense - and though I occasionally lost track of exactly who was who, I was never confused over where we were, or what was going on.

There are unexpected witty digressions: an appearance by the Duke and Duchess of Windsor is a particular highlight, as is a brief foray into the oeuvre of Jacques Brel. Georges’ faux-innocent artifice is nicely-drawn by Nathan, while Ida’s comic facial contortions bring life to the hard-bitten cat-burglar. The physicality is strong throughout, and there can be no doubt that the pair are charismatic performers.

But Tropez! isn’t quite there yet: it needs to tick up a level in speed and slickness to hit the comic heights it’s aiming for. It’s designed to deliver relentless fast-paced humour, but while the set-pieces are funny and effective, the fragmented narrative doesn’t build a great deal of momentum. It isn’t helped by some oddly laborious transitions, with the lights fading slowly in and out - though that could possibly have been a tech issue on the particular day I attended.

And when most of the characters are broadly-drawn stereotypes, there’s not much about them to connect with or root for. The exception is Dorothy, an elderly woman with an adventurous spirit, who’s come to Saint-Tropez with a poignant secret and a bittersweet goal in mind. That minor plot arc was touching as well as funny, and I think the show as a whole would benefit from a couple more like it.

Tropez! has an inspired scenario, some rewarding recurring motifs, and a nicely convoluted plot. So there’s a lot going for it, and a lot to enjoy. With some more pace and tightness, it’ll be a comedy diamond too.