Do you want to be a little boy or a little girl forever and ever, and to always have fun? Well then, let me tell you a story. Gather up your nostalgic imagination and fly with me to Never Land.

Set among a grove of trees, in a theatre open to the sky, find your way by fairy lights up into the gods. The deconstructed set – an astonishing accomplishment by Jon Bausor – is first glimpsed as a war-torn hospital scene, with army nets and trenches surrounding the raised stage. Young men are hospitalised in metal-framed beds and nurses attend. Wartime songs are spun around like echoes of another time (‘Keep the Home Fires Burning’ and ‘It’s a Long, Long Way to Tipperary’), along with the nymph-like presence of a singer (Rebecca Askew/Melanie Pappenheim) who delivers beautifully eerie, siren-like songs. The harpist, Tamara Young, deserves particular note for the astonishing dexterity of her playing, along with the dreamy musical arrangements of the original score by Nick Powell.

We soon emerge from this elegiac frame scene when a nurse begins to read Peter Pan to the soldiers. She, we discover, is Wendy (Kae Alexander). Never Land becomes a solace for wartime hurts and troubles, and thus is made far more enchanting than you could ever imagine or dream it; a childhood fantasia of springtime petals where adults are but a figment of the imagination, and flying through the air, entrancing creatures, and pirate baddies are the order of the day.

A particularly lovely moment occurs when we first meet Pan (Hiran Abeysekera), who is trying to catch his shadow, played by the soldiers. Abeysekera’s nimbleness and strength, displayed here, come into their own as he takes to the air with utter confidence. But for now, Wendy stitches on his shadow (only if he promises not to cry) and we get that first taste of his cheekiness, and far away innocence. The soldiers spin away to reveal ‘stitched-on’ shadows; a simple but seemingly magical creation of two spotlights.

The Lost Boys – dressed up in tie-dye jim jams, cosy knits and waist coats – are a troop of comic cuddles, yearning for a mother. Their accidents and ingenuity are a key figure in the amusing antics of Never Land. Thomas Pickles, as Slightly, is particularly endearing.

Tinkerbell is delightfully reimagined as a metallic puppet – a lamp and a brass kettle – whose grumblings and meddlings are more reminiscent of Puck or Wall-E than a Disney princess. Rachael Canning’s designs for the puppetry – fishes from pyjama bottoms, mermaids with gas mask faces, umbrella jellyfish – never fail to induce gasps of amazement.

I don’t suppose there could be a better adaptation of Peter Pan than has been achieved here at Regent’s Park Open Air Theatre – on stage, in film, in your wild spun dreams. Sheader and Steel’s vision puts the pantomime Pan of village halls far from our thoughts. With the cast of adult actors, we have sentiment without it cloying, and guilelessness without pretension. This is a daring and ingenious exhibition of how theatre can transfigure the old stories we know so well into an encounter so singular, we forget we ever knew the story at all.

Peter Pan is playing at Regent’s Park Open Air Theatre until 14 June. For more information and tickets, see the Regent’s Park Open Air Theatre website.