Joan Rivers, Theatre Royal, London

The second coming of the queen of bitchiness

When the warm-up act (Kit & the Widow, who add that touch of upper-class camp) sing a ditty that goes: "I honestly assumed she was dead", you can reasonably consider yourself in the presence of a show-business veteran. In front of an audience including more old queens than a certain recent funeral, Joan Rivers – introduced tonight by the ever-jolly Graham Norton (who apologises for being "another dreary homosexual") – makes her entrance clad in a silver blanket, like a London Marathon victim, and a pair of trainers, which she removes to reveal high heels.

At this point, she's probably won everyone over, before even one smutty line has left her lips. But Rivers so perfectly fits the tragic-icon stereotype, it's a surprise that she hasn't been reclaimed before. In the 15 years since her husband commited suicide and the loss of her regular TV slots, and at an age when any sensible wealthy widow would have settled down and vented her ire at targets viewed on a new television set, Rivers restored her fortunes with a series of self-help books and lectures and – oh, yes – a profitable range of jewellery, as seen frequently on the shopping channels.

It's a delight to be reminded, then, just what an acerbic stand-up Rivers actually is: energetic, ridiculous and completely shameless, like an older relative holding court at a tipsy family gathering. All right, some of her gags may have been going a bit grey around the time her forebears were fleeing Tsarist Russia, but such bitchiness can be counted as one of New York City's greatest contributions to humour.

And there are always new targets. Donatella Versace and "Celery" Clinton come in for a genteel booting, while the less-than-innocent Hilton sisters ("You know you're gonna catch something with them", accompanied by a grimace) receive the full force.

Her breathless discussions of the flatulence that afflicts all seniors, and the lack of dignified advertising roles for older actresses, point to a compulsion to go down raging against the dying of the light. And when the surgically recovered Rivers ("It would have been cheaper to have my DNA changed") reveals all about a birthday party held for New York's leading Botox doctor, attended by a stellar line-up of stiff-faced celebrities, we're with her simply for her frankness.

"Nana Newface", as she says her grandson calls her, ploughs on through an inevitable plug for her product (cue child labour gags) and concludes with a spectacularly tasteless post-11 September crack, on behalf of all the embittered widows who tragically struck gold. There may be "virtual" performers that look more lifelike than Rivers, but such effortless sniping will always have a future. Excellent.

6pm & 8.30pm on 21 & 28 April (0870 901 3356)