Rocky Horror Tribute, Royal Court, london

"Let's do the time warp again ..." Oh, alright, just the one more time, if you insist. Can you believe it? Fifty years after Look Back In Anger launched the English Stage Company at the Royal Court, the people's choice in a poll of their "favourite" play is nothing by Osborne, Wesker, Storey, Hampton, Churchill or Hare, but a sci-fi rock spoof that opened on 19 June, 1973 in the upstairs studio and became a cult classic.

As it happens, I was at that first late-night press show after attending a more "improving" performance in the main house of Edward Bond's The Sea starring Coral Browne and Ian Holm.

The sight of Tim Curry in fishnet stockings climbing over a gantry to lay his hands on Julie Covington and Chris Malcolm as the innocent mid-Westerners abroad abides with me still. What a relief, one felt. What larks.

"I'm a sweet transvestite from transsexual Transylvania" went Curry's glam-rock refrain as Frank N Furter, queen of the tempest-tossed castle. The Court had absorbed the alternative culture in plays by Heathcote Williams and Sam Shepard, but only "upstairs"; the director Jim Sharman and the author Richard O'Brien, who had met on the West End premiere of Jesus Christ Superstar then let rip on this glorious, unselfconscious rocky nonsense.

I think last night's extraordinary one-off gala concert - in aid of Amnesty International and the Royal Court itself - reminds present-day audiences that the Court has lately lost something it once relished, despite its serious mission as the home of new writing: its sense of fun, its sense of humour, its idea, perhaps, of "popularity." The show tuned into the era of David Bowie and Lou Reed and contains several numbers that really do stand the test of time; the film never really lived up to the stage show.

Last night, Richard O'Brien started by introducing the original producer, Michael "Chalky" White, in the stalls. Patricia Quinn, ever gorgeous like a red-haired Pre-Raphaelite, dripping with diamonds, sang the usherette Magenta's trademark "science fiction" song.

And we were away, with a funky band and cast members down the years coming, semi-costumed, to the microphone: Anthony Head as a brilliant Frank, more sexy than camp, Christopher Biggins winningly losing his lines as a narrator, Toyah Wilcox, all thunder thighs and tutu, as a new Magenta, Ade Edmondson reprising his definitive all-at-sea Brad.

Suddenly Biggins morphed into Robin Cousins, which was weird, then Head was deposed by Michael Ball and Jamie Theakston made an even more charming mess of his narrator stint than Biggins. As a concert, the event was terrific. I unreservedly withdraw my initial complaint that there were no good songs after the first half-hour.

"There's a Light" remains one of my favourite musical theatre songs. And Stephen Gately, formerly of Boyzone, bless, delivered a fantastic version. Most poignantly, the original Rocky, Rayner Bourton, whom I recall glistening in a gold jockstrap, declared his ageing with dignity.

So we got up and got down and boogied in the aisles, with skinny O'Brien leading the dance.