Thanks to a savvy marketing approach, advance sales for The Pirate Queen have topped €4 million, Moya Doherty and John McColgan tell Denis Staunton

She was a plundering warrior described as the "chief commander and director of thieves and murderers at sea" and a pioneering leader who battled with English administrators but formed an alliance with Queen Elizabeth I. Now Grace O'Malley, or Granuaile, has become the subject of a spectacular musical from the producers of Riverdance and the creators of Les Miserables and Miss Saigon.

The Pirate Queen started previews in Chicago on Monday and opens there at the end of this month before transferring to Broadway in April 2007. With a budget reliably reported to be more than $10 million (€8 million), the show has been four years in the making and could take a year or more to recoup its costs.

After the success of Riverdance, which continues to tour around the world, John McColgan and Moya Doherty were under pressure to produce a follow-up dance show, but decided instead to produce a musical.

"We wanted it be Irish, based on an Irish historical character, have an Irish sensibility," McColgan says. "We wanted it to be epic in scale. Second, we wanted someone who we felt could write something on that scale, and we decided that the people we wanted to work with and the people we've always admired in the world of modern musicals were Alain Boublil and Claude-Michel Schönberg.

"After much deliberation and discussion about whether it would be the Great O'Neill or Daniel O'Connell or Parnell - all these figures from history that might lend themselves to the world of musical theatre - we decided on Granuaile, Grace O'Malley, because we felt that she had the epic story, a great love story, her relationship with Elizabeth, all of that."

Set on the west coast of Ireland and in the court of Queen Elizabeth I, with sea battles in between, The Pirate Queen stars Stephanie H Block as Grace and Linda Balgord as Elizabeth. Eight Irish dancers have joined an ensemble of 12 Broadway dancers to produce an unlikely mixture of dance styles that choreographer Carol Leavy Joyce, herself a world champion Irish dancer, says are integrating seamlessly.

"Irish dance would have been much looser, much more free-flowing, much wilder, so that to me is very evident in telling the story, say, of a wedding in that period. So that's where I feel the actual gelling of the two styles, the contemporary style and the Irish style, has worked very well. Because they bring their looseness to it, they bring their acrobatic style to it and at the same time you have the Irish rhythm going consistently through it," she says.

Schönberg, who composed the music, took part in a series of workshops with traditional Irish musicians, visiting Dublin four times to explore the musical and emotional range of traditional instruments. Doherty says, however, that the result is a contemporary musical with an Irish flavour rather than a narrowly Irish experience.

"We hope to be creating an intelligent, entertaining piece of theatre that will have an international application. This is not being designed for any Irish-American audience, or for any American audience. It's being designed for a sophisticated theatrical audience," she says.

Doherty is also keen to pre-empt complaints by historical purists about the accuracy of the story told in The Pirate Queen, pointing out that the world of 16th-century Ireland has to be crammed into two hours of musical theatre. "It isn't a history lesson and this story is based on the life of Grace O'Malley. It is not the actual life of Grace O'Malley. We've taken from what we know exists in history but Alain and Claude-Michel have actually created their own Grace O'Malley, and the characters who surround her are really created from their imagination, based loosely on the history," she says.

Among the most intriguing elements of Grace O'Malley's story is her relationship with Elizabeth I, whose administrators she battled with but with whom she eventually allied herself. Balgord, whose high soprano distinguishes Elizabeth from all other characters in the show, acknowledges that the queen she plays is not strictly the monarch biographies portray.

"She's very decisive, which Elizabeth wasn't, from the research I've done. But for our purposes she's quite direct about what she wants done with Grace O'Malley. It's a very interesting parallel in our show with the story of Grace because they both really have to give up a great deal for their people," she says.

With spectacular battles and aerial fights, The Pirate Queen is so technically complex that preview-goers are likely to see only a scaled-down version. Changes are likely throughout the run in Chicago before the show is "frozen" about 10 days before it opens in New York.

Opening outside New York is traditional for musicals, but McColgan and Doherty have devised a non-traditional strategy for boosting ticket sales before the move to Broadway.

"We were sitting in a marketing meeting in Chicago about three or four months ago when one of the figures that came out was that 40 per cent of bookings for Broadway shows nowadays come via the internet and it's sometimes up to 60 per cent," says McColgan.

"This triggered a thought in us - if that is the case, why can we not use that in a more creative and intelligent way to speak directly to potential theatre-goers via the web . . . that we should engage with people who go on a website."

Drawing on their background in television, the producers are broadcasting on the show's website a reality TV-style diary of the making of the musical, with interviews with performers and other members of the creative team. The scheme appears to be working because, more than six months away from opening night on Broadway, The Pirate Queen has already taken more than $5 million (€4 million) in advance sales.

Musicals can, of course, go spectacularly wrong, and New York critics can be merciless about original shows, prompting many producers to choose the safer option of "jukebox musicals" based on well-known hits. Doherty is hoping the critics will like The Pirate Queen but she points out that they don't always have the last word when it comes to success or failure.

"One very good example is Wicked, which was absolutely panned by the critics and it is the biggest hit in the past five to six years in musical theatre. It's sitting here in Chicago, it's been sitting for a year. It opened in the West End. It captured the imagination of the audience and they completely ignored what the critics said."

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