At first thought, you might decide that Arthur Ransome’s stories about middle-class children having boating adventures at the start of the 1930s were pretty irrelevant in the 2010s. But they’re not. The Swallows and Amazons series is still much read by its intended age-group and – which is even more important – much loved.

This adaptation by Helen Edmundson of the book which started it all takes the audience effortlessly into Ransome’s finely-crafted world through a production by Tom Morris} which balances the natural with the expressionistic through [Robert Innes Hopkins’s deceptively minimalist setting and Neil Hannon’s haunting score. After all, letting the imagination loose to work its own magic is a well-pedigreed theatrical technique.

The child characters are all played by actors who can make the young audience suspend any disbelief within a couple of minutes; their elders are also the musicians who double as seen-but-understood-to-be-ignored shifters of boats and other props. The Walker children (in order of seniority) are Richard Holt as John, Katie Moore as Susan, Akiya Henry as Titty and Stewart Wright as Roger. Celia Adams and Sophie Waller play the Blackett girls, the Amazons of the title.

One crucial misunderstanding driving the plot concerns the Blackett girls’ uncle (Greg Barnett), a writer with a houseboat. As the crew of the Swallow rise to the Amazons’ challenge, we watch the adventures with enjoyment and learn that the best of intentions doesn’t always meet with success. There’s a real sense that water is an environment to be enjoyed but also to be treated with respect and that certain actions to have unforeseen consequences.

That may make it seem like a morality tale. It’s not, though it does have morals as well as a moral. Not a bad thing. Two and a half hours (including an interval) is quite long for a children’s play, but the young members of the Norwich audience stayed gripped by both the story and its presentation; full of questions for their elders as they left the theatre. The Lake District may just have acquired some new fans.