Of course, a lot has changed since then. She has sold more than 200 million albums, changed pop culture for ever, done some severe depilation work on those eyebrows and had a frankly astonishing 58 singles in the UK Top Ten. You might want to spend a moment compiling a list of them in your head. It’s a pretty impressive spread.

But Madonna isn’t the only one to have undergone radical change in the past two decades. This, the shabby end of Camden High Street, was decked out, for one night only, with glitterballs on the streetlights. This is the power of Madonna — she managed to make the sad crossroads of Mornington Cresent kebab shops and legal advice centres look like a thrilling New York disco nexus from 1979.

When she finally took to the stage, resplendent in purple knickerbockers, purple knee-high boots and blonde flicks 40 minutes late — mere peanuts to the 200 fans who camped out overnight for tickets — she was greeted with a World Cup goal roar. And little wonder: the current, resurgent Confessions From A Dancefloor album is one of the all-time great pop World Cup goals.

Never one to shilly-shally, Madonna launched straight into the present No 1 single Hung Up, which had the audience screaming as if they were being tortured, but in a good way.

“It’s f***-ing great to be back here!” she yelled, throwing her sunglasses to a perfectly positioned sunglasses roadie.

The proof of how universally loved Madonna is in 2005 came in the truly bizarre make-up of her audience. A 70-year-old man in a blazer; Graham le Saux; an otherwise very straight man wearing a towel round his neck, in homage to the video to Hung Up; Bob Geldof looking like a vengeful Gandalf being forced to dance to the DJ’s amyl-house set by his daughter Peaches; a man in a toga; Stella McCartney; a respectable-looking matron in an anorak embroidered with horses; Frankie Dettori.

There was much speculation over whether Madonna’s vocals would be live. Compared to the undeniably live honk-fest she turned in at the European Music Awards, both Hung Up and the subsequent Daft Punk-ish Get Together sounded suspiciously pristine. However, both Madonna’s hair and Madonna-ness were undoubtedly live, which is the important thing. Launching into her third number — I Love New York, accompanied by a squad of street-dancers and a backdrop of New York skyscrapers — Madonna’s voice became endearingly honking again.

Of course, some might say that doing a mere 20-minute set composed entirely of new material is not quite the act of pop munificence one would hope for in this key week of Madonna’s success — especially as the set was cut short so that she could sing at a subsequent “intimate gathering” for the European heads of Warner Music.

Ending with Everybody, she got the audience to chant “Dancing Queen go and do your thing” at her while she busted some frankly impressive moves in a feather boa, beaming like a happy kid and still not breaking a sweat.

“Thank you, London,” she screamed as a gigantic glitter-cannon exploded in the ceiling, shedding two tons of glitter across the Koko and making the whole audience look gay.

And really that’s Madonna’s modus operandi in a nutshell.

Editor's choice

• Desperados with avocados - a sort of Guy Ritchie film
• Live fast, die young: The 27 Club
• Madonna's 50 most memorable moments