Swallows and Amazons

Claude Watham's classic film of Arthur Ransome's 'Swallows and Amazons' book ought to be as beloved as 'The Railway Children'. It is the tale that launched a thousand imaginary ships. Any theatrical adaptation would have to be very special to extend the pleasure of this 1920s children's fantasy of playing at pirates with real boats in the Lake District.

At first, you do wonder who this Bristol Old Vic/National Theatre musical adaptation is for: grown men and women play the pre-pubescent crews of the Swallow (four nicely brought-up London holidaymakers) and the Amazon (two chippy Northern lasses). Plus, the detailed realism of the novel and the film are discarded for oversized play (Roger, the seven-year-old youngest of the Swallows, is a bearded six-footer).

But theatrical magic ingeniously solves all practical difficulties and Tom Morris's production is one in which everyone is invited to play.

The Divine Comedy's Neil Hannon's infectious yet discreet songs do a lovely job of expressing the free imaginative life of the children and the subtext of their anxiety in a holiday world where adults are 'barbarians', mum and dad are absent and adored, and youngsters are marvellously self-sufficient. The Amazon 'pirates' are especially vivid; snarling girls, neglected by their beloved uncle, they play brilliantly as themselves and as the bloodthirsty revengers they wish they were.

Helen Edmundson's stage adaptation sails into your imagination. A feather duster and a pair of secateurs become a parrot. Dreams come to flamboyant life on stage. And a talented blue-coated musical ensemble play the minor characters to perfection.

The final naval battle, in which missiles are hurled by the audience at the Amazons' dastardly uncle, is guaranteed to win small hearts and minds. But the humour, intimacy and ingenuity of this theatrical adventure will bring them on board long before the cannonball-chucking finale.