In 1980, when David Edgar's ground-breaking adaptation of Charles Dickens's third novel was first staged, it was hailed as one of the great events of modern theatre, a play which fractured "all the petty limitations we have imposed upon the stage".

Produced by the RSC with a run time of over eight hours, it also became the first piece of drama to be seen on Channel 4 television.

Now, more than 25 years later, Chichester are undertaking its first major restaging. The reduced script has been substantially rewritten by Edgar himself and clocks in at just over six hours, spread over two plays.

But it still involves 23 actors playing more than 100 parts and promises to be a theatrical experience of rare scope and genuine scale.

"It's a copper-bottomed masterpiece," declares Philip Franks, who shares the colossal task of directing with Jonathan Church, the Festival's new artistic director.

"I just think it's completely brilliant. It's a wonderful book in the first place but it's the best adaptation of any novel that I've come across because it embraces the sweep and variety and huge mood changes of Dickens. It doesn't try to squeeze it into a pint pot. This is huge."

Taking in a wedding, a hanging and a duel to the death as well as numerous preposterous coincidences, abrupt reversals of fortune and collisions of good and evil, The Life And Adventures Of Nicholas Nickleby charts the journey of a poor young man through 1830s England.

From schoolteacher in Yorkshire to actor in Portsmouth, along the way he befriends the crippled Smike and encounters a variety of eccentric characters, including the tyrannical Wackford Squeers, master of Dotheboy's Hall.

"I tried to tot up how many parts there were and got lost around 160," laughs Franks, who you'll recognise from Darling Buds Of May and Countdown's Dictionary Corner.

"Everybody has got a dog-eared piece of paper in their pocket without which they're doomed - At this point I come off as the milliner and have 40 seconds to change before I come back on as the starving boy, then I've got a whole scene off before I return as a chimney sweep'.

"Even Smike has a dazzling little cameo as the croupier in a casino in Part Two. Nicholas himself is played by the 27- year-old Daniel Weyman, a newcomer chosen for his "wonderful, open, earnest intensity", while established cast members include Dilys Lays and Leigh Lawson.

The set Franks describes as "a cross between a jigsaw and an advent calender", a London rat-run of windows and doors, staircases and walkways from which a thrust comes "zooming out like a giant tongue, serving the actors up into the audience".

When Franks undertook the challenge of directing this epic production, it seemed, he says like an "unscalable mountain made of glass". But he was confident, all along, of Dickens's suitability for the stage.

"I think the main reason he works so well on stage is because he had an absolutely passionate love of his audience," he observes.

"Some writers write for themselves, others write for a coterie - Dickens wrote to get as many people laughing and crying and trying to change the world as he possibly could."

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