Over the last 20 years or so West End theatre producers have discovered the commercial potential of turning so-called children's stories into blockbuster musicals.
Beauty and the Beast, The Lion King, Mary Poppins, Shrek, Chitty Chitty Bang Bang and The Wizard of Oz immediately spring to mind. Lord of the Rings almost fits the pattern too.
Common to all these titles is the fact that film versions have preceded the theatre musicals, thereby embedding them into a wide public consciousness, so that warm, nostalgic bells ring at their mere mention. The arrival of Matilda the Musical and Charlie and the Chocolate Factory is a natural progression.
Roald Dahl's stories are still huge favourites amongst children. Both books and the film versions. But, more importantly marketing-wise, their parents and even young grandparents remember them with great affection. They are innately theatrical, with larger than life characters, life and death situations, brilliant baddies, child protagonists we can all (not just children) identify with, joyous irreverent humour, an emotionally satisfying sense of justice and often an alluring use of magic.
Dahl is in the tradition of the classic storytellers, using giants, witches, animals and insects, dramatic shifts of scale and the supernatural, all cleverly woven into stories that feel contemporary, yet are timeless.
Over the same 20 years or so, I have been privileged to adapt Dahl's stories from page to stage - the tally is now eight - but my adaptations are plays, not musicals. They are performed professionally all over the world. The BFG has toured the UK several times, and has played three West End seasons, as has The Witches.
The Belgrade Theatre, Coventry, the Sherman Theatre, Cardiff and Birmingham Stage Company have commissioned, toured and brought to London The Twits, Fantastic Mr Fox, James and the Giant Peach, Danny the Champion of the World and George's Marvellous Medicine.
Huge numbers of schoolchildren in parties, plus family groups, have seen these plays in theatres throughout the UK. Indeed, the Birmingham Stage Company's production of James and the Giant Peach, directed with panache by Nikolai Foster, is currently on tour.
As a children's dramatist, I wrote these adaptations - as I believe Dahl did in his books - for children first and foremost. I didn't try to broaden them by putting in stuff for the grown-ups. Yet it is fair to say that lots of grown-ups, not just teachers, are in the audience whenever we tour a Dahl. This adult appeal explains why producers can safely schedule 7pm performances, unlike most of my children's plays which play matinées only.
Of course my adaptations, though by no means simplistic (The Witches contains some spectacular Paul Kieve illusions), are not conceived on the huge scale of a blockbuster musical, with very large casts and complex technical wizardry. But this means they can tour comfortably to most regional theatres, and are also attractive to community companies and school drama groups, who put on their own productions.
This coming Christmas, for instance, The BFG will be playing professionally at Dundee Rep and at Trinity Arts, Tunbridge Wells and The Witches, featuring Chichester Youth Theatre, will be the Festival Theatre's seasonal offering. The Magic Finger, my most recent Dahl adaptation, has just finished its premiere season at Imagination Stage, the children's theatre in Washington DC - Dahl is increasingly popular in the United States.
Matilda the Musical and Charlie and the Chocolate Factory's musical makeovers are very welcome in the West End and will hopefully be here for a long time. And I am sure that more large-scale Dahl musicals will follow.
But London is too far away for many children to be able to come and see these productions. Hopefully my play versions of the Dahl classics will continue to reach children wherever they live and introduce even more of them to the pleasures of theatre-going.