What’s that, up in the sky? Is it a bird? Is it a badger? No, it’s Brian May, ascending from the top of a stage built around the Queen Victoria Memorial. He’s playing the solo to “We Will Rock You”, accompanied by a legion of Royal Guard drummers, all hammering out the handclap beat and making Freddie Mercury moustaches with their drumsticks. As the ancient scripture says, when Brian May rises above Buckingham Palace, let the joobs commence.

Following an afternoon glugging Majtinis with the very same people who’ll be stealing their wheelie bin next week, flag-wavers in their thousands throng The Mall for a live concert of music, dance and unfathomable weirdness. It’s all to celebrate 70 years of involuntary servitude to a woman at the head of a family accustomed to using our money to buy themselves out of legal trouble. Huzzah! Thank you, ma’am! Partygate, what Partygate?

As the show begins with a touching skit of the queen taking tea with Paddington Bear, we might expect a fairly safe, comfy, nonagenarian-friendly sort of evening – George Ezra, Elton, Rod, Diana Ross. The Kunts are presumably clapped up in the tower for the duration. But what we, and an increasingly dumbstruck stand full of royals, get is one of the most bizarre and unrelenting barrages of random entertainment ever staged.