High heels skitter over the cobbled courtyard and we join the line behind tiny ladies in ancient minks and young men in blazers and ponytails. As the day-trippers leave Versailles in their monstrous coaches, the opera crowd enters the 18th-century corridors, now equipped with temporary cloakrooms and portable champagne bars.

It feels like a privilege, even if we have paid a goodly sum, to be let loose in the palace of Versailles on a sunny evening. A few hours earlier we were the tourists; now we are the elite, striding through the marble corridors, glimpsing the breathtaking chapel on our way to the Opéra Royal. We’re directed round the curved stone walls that enfold the tiny wooden theatre and in through a low door (we’ve all grown a bit since the 18th century). And there it is, like a Pollock’s toy theatre, pastel-blue walls, gilded swags and balconies as far as the eye can see, right up to the cherubs on the painted ceiling. Golden pillars support the royal balcony and giant chandeliers light the auditorium. And yet it’s oddly restrained compared with the monstrous bling of the state apartments and the miles of topiary and water features that surround the estate.

The opera house was completed in 1770 by the Sun King’s son, Louis XV, and the seating hasn’t changed much since then. An inch of plush has been added to the hard wooden benches, and we’re thigh to thigh with our Parisian neighbours, unprotected by crinolines. The middle-aged man next to me is wearing artfully ripped jeans; the woman in front has unearthed a burgundy frock from a couture house circa 1982. We’re regretfully informed that Vivica Genaux is ‘très malade’ and is ‘désolé’ not to be able to sing tonight, but instead we have the lovely Blandine Staskiewicz singing Rossane. I’m unfamiliar with both Blandine and Rossane – I haven’t read up on the plot, but I’m so excited to be seeing a staged production in this lovely little theatre that I don’t really mind. You can’t go wrong with Handel – can you?

By the interval, I’ve decided that Alessandro is not one of his best operas, although it’s very pleasant to listen to while you’re staring around this wonderful theatre. The orchestra is the young Greek ensemble, Armonia Atenea, all potential soloists who play brightly for their charismatic conductor George Petrou. The production is by legendary American choreographer Lucinda Childs – the one who made Glass’s interminable Einstein on the Beach such an arresting spectacle. Childs hasn’t taken the plot too seriously, opting instead for hammed-up characterisation, lovely interludes with a few nimble dancers and plenty of campery and visual gags. And it works. After the excess of statuary in the marble corridors outside the theatre, seeing a six-foot-plus bass dressed in a skirt doing high-kicks in a chorus line seems almost normal.

Childs employed the old ‘play within a play’ trick, so the story of Alessandro is being filmed in the silent movie era as a Cecil B DeMille-style biblical epic. Handel didn’t waste time creating rounded characters; he chose a plot that would reflect the real-life rivalry of two star Italian sopranos of the day, Faustina Bordoni and Francesca Cuzzoni. In Childs’s version the leading man is attempting to string along both leading ladies, resulting in a series of catfights and a lot of flouncing around the dressing rooms (and that’s just Alessandro). There are fabulous frocks and showy coloratura from Blandine Staskiewicz as the blonde, Rossane and Adriana Kučerová as the brunette, Lisaura.

Much has been written about Max Emanuel Cencic’s extraordinary, soprano-like countertenor but even in this tiny auditorium it sounded underpowered when he was not at the front of the stage. A beefier and more satisfying countertenor was Xavier Sabata as Tassile, King of the Indies. With a cast that includes three countertenors and two sopranos, the register is unremittingly high and light and it is a relief to hear the earthier depth of the bass Pavel Kudinov as Cleone. The other roles were notable only for a scene at the neon-lit Handel’s Bar where they perched on stools, plotted against their leader and tried to stop their skirts riding up and exposing their knickers. Now you know how it feels, guys.

Alessandro opened in Wiesbaden and goes on to Athens, but it was obviously tailor-made for Louis IX’s gilded fantasy, Versailles. From Alessandro’s golden six-pack breastplate to his courtiers’ satin kilts, the whole production was an over-the-top celebration of artifice, theatricality and history-lite – just like the Sun King himself.

A recording of Alessandro by Armonia Atenea and Max Emanuel Cencic is available on Decca Classics.