Wicked: tales of the witches of Oz

The 'untold' story of the witches of Oz cast a spell on Broadway. Now it's coming to London. Nicola Christie follows the musical's yellow brick road to success

The West End is about to go green. Not in the ecological sense but as in witches' skin colouring.

There's a show preparing to fly in - two witches are gearing up on broomsticks right this moment ahead of their September premiere - that will launch itself with such gusto that at least half of the London buses and taxis are likely to get a thick lick of green paint. When it announced itself in London in March, the West End venue used to herald its arrival was entirely relit, greenlit, for the purpose.

Wicked began life on Broadway in October 2003: a new musical offering itself as the untold story of the witches in the Wizard of Oz. It would focus in particular on the Wicked Witch of the West. And it would ask how she came to be green, how she came to be wicked, who decided that she was wicked anyway - along with the necessary backstories to Dorothy, ruby slippers, yellow bricks and men of tin and straw.

The show is currently in rehearsal at London's 3 Mills film studios. It's the only space big enough to house the staggering scale of the production - whose $14m dollar initial investment was reclaimed in the first year on Broadway alone. In London, it will open at the Apollo Theatre in Victoria. It comes from the Gershwin Theatre, 222 West 51st Street, Broadway's largest, which sells out its 1,850 seats daily.

"For the past 20 years we haven't seen anything like it on Broadway," says David Cote, theatre editor of Time Out New York, "not since the Cats and Phantom of the Eighties - in terms of a production's potential to be such a long-running and international hit. Sure, Broadway's been healthy recently with musical comedies like The Producers and they too are doing national tours, but not doing sit-down runs - which are basically open-ended runs - like Wicked. Wicked has become a phenomenon that no one had anticipated."

It's likely that the authors of this tale, all of them, hadn't anticipated it either. Let's start with the first.

L Frank Baum. Born 1856; deceased 1919. In 1900 he wrote a story about a young girl, a yellow brick road, a tin man, a scarecrow and a lion. He called it The Wonderful Wizard of Oz.

In 1939, Victor Fleming put this story on to the big screen, making a star of actress Judy Garland; and spawning rumours of Hollywood hell behind the scenes, pepping the actors up on pills and locking the munchkin dwarf actors away in some dodgy hotel; material which Scottish playwright Irvine Welsh is enjoying in his new play, Babylon Heights, which has just opened in Dublin.

In the early Nineties an American novelist, Gregory Maguire, decided to rewrite L Frank Baum's story. He happened to be living in London at the time, and he had already enjoyed much success reworking fairy tales for children. A new city triggered a new idea: why not have a go at the ultimate fairy tale (in the US its status is something akin to that we have afforded Alice in Wonderland) but this time write it for adults. Maguire would ditch Dorothy and offer centre stage to the Wicked Witch of the West instead. His main concern was to defend her, find out who the little girl was who ended up green and holed up in a tower with monkeys flying around her. When did someone title her "wicked"? And was she deserving of this title?

Maguire's novel was more dark than comic, an adult read reflecting on the nature of being an outcast, society's pressures to conform, and the effects of oppression and fascism - the Wizard moves from charlatan to dictator in his story.

The book ended up in the hands of Marc Platt, a producer from Universal Pictures. Platt optioned the rights immediately, seeing the tale play out on a big screen before him as the pages turned. But US composer/lyricist Stephen Schwartz, who had enjoyed success with scores to Disney movies such as Pocahontas and The Hunchback of Notre Dame, begged Platt to rethink his adaptation.

"One day Stephen called me and said 'I understand you're developing a film based on Wicked'," says Platt. " 'Did you ever think of turning it into a musical?' he asked me. A light bulb went off in my head and I thought, that's what's missing."

And so a musical of Wicked came into vision. A writer of various hit US TV series, Winnie Holzman, was hired to come up with the book; Joe Mantello - more known as an actor than a director - got the gig of directing this extravaganza; and Eugene Lee was asked to build the new Emerald City on stage.

The result is highly impressive. During a week in June, when I went to Broadway shows back to back, including Avenue Q, Wicked stood out by miles. It was the only one which genuinely took my breath away, gave me the lift-descending tummy swoops, that only a true musical can.

It's the scale of it which immediately impresses. A large canvas old-world map of Oz greets the audience on entering the auditorium. A giant, intricately detailed set, which looks like the inner workings of a clock, is suspended all around.

Stephen Schwartz's score is on an equal scale, combining cheeky bouncy numbers with soul-searching mighty anthems such as "Defying Gravity": the closing song to Act 1 which Elphaba - the young Wicked Witch of the West, whose name is a phonetic take on Baum's initials - belts out while discovering her powers (she can fly).

" 'Defying Gravity' works perfectly on your nervous system," says Cote. "It sort of gets you excited and hopeful and a little fearful at the same time - it plays on your emotions very nicely, which is what great songs from a musical should do. But some of the other numbers are harder. I'd describe it overall as a mix of pop and quasi-operatic styles."

British actress Miriam Margolyes, who has landed the gift role of Madame Morrible, the caustic headmistress of the boarding school where Elphaba and Glinda (the Good Witch who is not so good) meet - "I'm basing her on a mix of my headmistress and Mae West" - is getting fitted for her costumes at the moment.

"They are absolutely sensational," she says. "They're so complicated that they needed me to fly back from my holiday in Australia for one day to have a fitting. They're based in a way on Edwardian costumes but they're very, very strange shapes with buckles and trains, and I'm going to be wearing a corset all the time. They're not like any costumes of a headmistress I have known. She's definitely a creature from another world."

Whether Wicked will manage to translate to the UK and beat the competition is hard to judge. But it deserves to.

'Wicked' opens at London's Apollo Victoria Theatre (0870 4000 889) on 27 September, previews from 7 September