ALAN Ayckbourn's The Boy Who Fell Into A Book is now also Paul James, Cathy Shostak and Eric Angus's The Boy Who Fell Into A Musical Book.

It may be sacrilege to suggest you can improve on an Ayckbourn piece, except for the occasion when Ayckbourn and Andrew Lloyd Webber revived and revised their flop 1975 musical Jeeves as By Jeeves to mark the Stephen Joseph Theatre's move into the old Odeon building in 1996.

However, "The Boy" lands between the leaves again 16 years after its 1998 debut all the better for its new musical setting as it tells of the world-saving quest of an incongruous pair: ten-year-old book enthusiast Kevin Carter and his fictional hero, Rockfist Slim, one of those hard-bitten private investigators whose every utterance is the stuff of a comic-book speech bubble.

North Easterners Paul James and Eric Angus and New Yorker Cathy Shostak had met at a London music theatre writers' group, going on to write The Demon Headmaster, and when looking for another project, Shostak had a "light-bulb moment" as she read "The Boy".

Angus agreed it would be perfect for a musical with its "strong characters, great set-pieces and a variety of fun settings", while James saw it as "a buddy move, a road trip, a quest where two unlikely partners must learn to co-operate to survive", as well as an "enjoyable meditation on childhood, the act of reading and imagination".

It was indeed all those things already, and when Ayckbourn heard demos of early songs, especially the very first witty pastiche they wrote, Kaboom! Kapow!, he had a hunch the show would work anew and agreed to direct it. Lucky Paul, Cathy and Eric, and lucky Scarborough summer audiences too because this is a wonderfully inventive production, cast superbly well.

The "Boy", Kevin, is played by an Evelyn but not of the Waugh variety, so much as by an actress in pyjamas, Evelyn Hoskins, who captures the inquisitive, plucky essence of a boy who likes to read beneath the duvet beyond lights out and treats slipping into the world of books as a glorious adventure.

There he meets Nicolas Colicos's Rockfist Slim, the essence of the American gumshoe in mac, trilby and correspondent brogues, who has only 72 hours to thwart glamorous French villain Monique (Katie Bartill). Kevin is happy to help in these pyjama dramas as long as he can be home in time for reading in bed.

Songs both illuminate what they are thinking and move the story forward. Make that stories, because they slip into ever stranger, surrealist encounters with Chess For Beginners' medieval Red Bishop, the Grimm Brothers' Rumpelstiltskin (Stephen Matthews); and Scottish Jennet from Kidnapped (Natasha J Barnes).

This is why The Boy will appeal to adults and children alike, whether for the literary references or the visual daftness of the big, blubbery, jelly-loving Wubblies.

Not only will you fall in love with Ayckbourn's book world all over again, but this time you will go home singing Kaboom! Kapow! too.

The Boy Who Fell Into A Book, Stephen Joseph Theatre, Scarborough, on various dates until August 31. Box office: 01723 370541 or at sjt.uk.com