Spice Girls, O2 Arena, London

As it was for many teenage girls, "Wannabe" was the soundtrack to my summer of '96 my first holiday with my then best friend and our first foray into clubbing. Then, the Girl Power ethos reigned supreme. The Spice Girls the most successful all-female band to this day with nine No 1 singles and 55 million albums sold had the brains and ambition behind the looks. And we, with our whole lives and careers ahead of us, had our dreams.

And, when the returned popstars arise on five podiums to deafening screams for their first UK show in nine years, most of the 20,000 fans are drawn into a time warp for the two hours and 22 songs to come.

As they launch into "Spice Up Your Life" to deafening screams, I can taste my first sip of Malibu and pineapple. As they perch and pose in their Roberto Cavalli costumes, Geri Halliwell yells: "Are you ready for some Girl Power?" and Emma Bunton, who, despite spraining her ankle during a show in Las Vegas just days ago, performs in high heels, cries: "It's so good to be home. We're back together again!" "What a crowd. We love you London!" adds Halliwell.

The enthusiasm is genuine; throughout their energised show they wrap arms around each other, smiling and giggling. But the biggest screams are reserved for Posh Spice, whose first, tentative, solo in "Stop", causes the crowd to erupt though probably not in response to her vocal talent. The crowd, which snapped up Saturday's tickets in 38 seconds, keep up their long-hidden dance moves. Despite the usual question over whether the girls would be miming, the odd slightly off-key note suggest the singing is live.

The sway-inducing fourth song "Headlines (Friendship Never Ends)" is slow, but they regain the interest of the crowd with one of the many inventive stage sets. The impressively choreographed dance routine that accompanies "Lady is a Vamp" from the 1997 album Spiceworld is followed by a sped up version of "Too Much". "2 Become 1" even sees them mildly toying with pole-dancing on a stage filled with giant feathered fans. But they can do sentiment as well as irreverence: in "Mama", a choir of 50 young girls in angelic white dresses line the stage against a backdrop of the stars with their mothers and their own children.

They recreate their glory days with their signature costumes for a fantastic performance of "Who Do you Think You Are?"; Scary in a leopard-print body suit, Ginger in her Union Flag mini, Sporty in crop-top, Baby in shiny sugar-pink trenchcoat, and Posh in a lacy black dress. It's ingeniously topped by Posh self parodying her celebrity status as she struts the walkway in sunglasses with a mobile phone and a black silk cape billowing behind her.

The other four get their solo moments too, Halliwell storming the stage in a red leotard to "It's Raining Men", and Mel B living up to her "Scary" label as a dominatrix performing Jimi Hendrix's "Are You Gonna Go My Way?".

As ever, it is Mel C who can compel with her vocals alone. Her single "I Turn to You" is the only song performed alone onstage.

Entertaining at every moment, even to the end with their celebratory encore of "Wannabe", the Spice Girls tell a remarkable story of success, summed up in the final big screen message: Mission Accomplished.