Were it not for the spirited, sinuous and stylish playing of Sir John Eliot Gardiner’s period-instrument orchestra, the English Baroque Soloists, you wouldn’t find even two stars above this review. I loved the way that Gardiner and his musicians - raised several feet above normal pit level, to thrilling effect - lavished as much energy and finesse on this intermittently prophetic but diffuse Mozart comedy (written when he was 18) as they would have done on“Figaro”.

But as for what went on above their heads - oh dear. Not so much “The Pretend Gardener” as the pretend staging: a farrago of inconsequential modern-dress posturing, hammier than a convention of butchers, stuck in one of the dreariest sets I’ve seen at Covent Garden.

You know you’re trapped in a dismal evening when the tenor starts splashing in an onstage pond to raise a cheap laugh.

Admittedly, the Royal Opera has had well-publicised problems preparing this show. Gardiner and the intended stage director, Christof Loy, disagreed over what cuts to make in the long-winded score. Loy walked out, leaving his assistant, Annika Haller, to recreate a staging Loy devised eight years ago in Dusseldorf - if you can believe such tosh. And this is billed as Covent Garden’s first “new”, production of the season? God preserve us.

But could any staging make something dramatically credible of this plot? It’s a creaky tale of a noblewoman who disguises herself as a gardener to escape from her violent lover, only to fall for him again when he reappears to woo somebody else. However, the opera does have two unexpectedly poignant scenes when both central characters go poetically mad. With sensitive handling, the piece could be presented as a forerunner to “Cosi fan tutte”: a study of lovers who locate their true feelings only when driven to despair and confusion.

No chance of that with characters rushing like demented clockwork dolls, doing utterly pointless bits of“business”. Some of the singing sent the wrong sort of shivers down the spine, too. In the title-role Genia Kuhmeier was too often below pitch and hooty. Camilla Tilling, as her aristocratic rival, was better vocally but all over the place as a character.

Sophie Koch seemed to have problems with any sort of coloratura in the breeches role of Ramiro. Kurt Streit was at least dependably loud as the perpetually harassed Mayor. But it was left to Patrizia Biccire as the maid and Christopher Maltman as her continually repulsed lover to generate what comic momentum there was, with Robert Murray as the two-timing Count Belfiore supplying the evening’s most elegant singing.

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