Asked what Wicked is about, the author of the original novel, Gregory Maguire, says, "Donning my English professor cap, it's about the cost, both to the individual and to the society, of being different".

It's an idea many people can identify with, and maybe that's part of the reason for Wicked's appeal. The 1995 novel – which Maguire wrote as an alternative history to L. Frank Baum's The Wonderful Wizard of Oz – was his biggest success and has spawned three sequels.

Maguire, who earned his doctorate in children's literature, says The Wonderful Wizard of Oz is "one of the foundation documents" of that genre and of American literature.

And it may even be broader than that: he sees it, too, as being in the vein of Daniel Defoe's Robinson Crusoe, with its theme of self-reliance, and points out it's a text in which you don't have to be high born to live a just and brave life. And, of course, the 1939 film adaptation The Wizard of Oz brought the story even greater popularity.

Maguire wanted to draw on these stories to explore some political and social themes in his novel, presented as an alternative history (subtitle: The Life and Times of the Wicked Witch of the West) telling a very different story to the one already known and reminding readers that what we're told is shaped by who's telling it as well as what we already think, know and believe.

It also inspired the 2003 Broadway musical of the same name with a score by veteran composer Stephen Schwartz, whose earlier shows include Godspell and Pippin. Wicked is having its Canberra premiere this month with a cast combining three professional lead actors with some seasoned Canberra talents and is directed by Shaun Rennie. The actor and director was last seen in Canberra playing Bert in Free-Rain's Mary Poppins.

Wicked: The Untold Stories of the Witches of Oz, the musical, is necessarily narrower in focus than Maguire's much longer – and darker – book, which covered a lot more ground in more adult-oriented detail.

Told in flashback in Oz after the death of the Wicked Witch of the West, the musical relates how Elphaba (played by Loren Hunter, with Kirrah Amosa as alternate), a green-skinned, awkward and poor young woman is forced by the headmistress, Madam Morrible (Bronwyn Sullivan), to become roommates with popular, wealthy Galinda (Laura Murphy), at Shiz University. While this makes both of them unhappy at first, a bond gradually forms between them. They meet other students, including the roguish prince Fiyero (Drew Weston) and grow uneasy at the persecution of the talking Animals including one of their own professors, Dr Dillamond (Fraser Findlay). They decide to ask the Wizard of Oz (Steve Amosa) to put a stop to the oppression. But it's not as simple as all that.

Maguire says of the stage version, "As a work of theatre and a work of art I admire it a large amount."

"The first time I saw it in front of an audience was in June 2003 in San Francisco during an eight or 10-week run," he says. This was its pre-Broadway tryout and though he had heard songs before and seen script pages, he was blown away by the special effects, the staging and the enthusiastic response of the audience.

The show's writers made some alterations during that preview period – notably, Fiyero's opening number, Which Way's the Party, became Dancing Through Life.

Maguire understood that in the process of adapting a literary work to another medium, a lot has to be jettisoned or changed. But, perturbed by some of the radical alterations to his story, he prepared a few pages of notes – "I thought they turned it from a tragedy into a bittersweet morality play" – only to be politely ignored. And he acknowledges now that a more faithful adaptation of his novel would probably not have been as successful and also that the adapters did manage to convey the same essential messages as the book – "Life is about the choices we have to make and the people we have and to do what is right ... It's still the same messages, that's all that counts."

Ever since Schwartz had told him the first song in the show was to be called No One Mourns the Wicked, Maguire says, it seemed like they were sufficiently compatible: whatever else happened, that central theme of being different, and the effects it had on the one who was different and on everyone around them, would come out.

Wicked, the book, has spawned three sequels and their success and that of the musical has enabled Maguire to explore other writing interests. He's adamant that his time in the Land of Oz is over.

"I'm done," he says. But he's not finished with the concept of revisionism of well-known stories, it seems.

"I'm writing a new book at the moment, based on a fairly familiar story popularly told around Christmas time."