The four stories in the Paradise Barn quartet take place in a fictional country town called Great Deeping.

Many of you will not need to know any more than that. But, if you enjoy looking at maps, you might like to know that when I first imagined Great Deeping I placed it in the Fens, several miles north of Ely. It is halfway between Littleport and Southery (which do exist). The Fens are very flat, with wide open fields and enormous skies. Long ago, most of the countryside was under water and Great Deeping was then an island.

There is a railway station there (it comes into all of the stories) and trains come from Cambridge and Liverpool Street and continue north to Kings Lynn. Its river is the Great Ouse, and the river and the railway run more or less side by side as they skirt the eastern edge of the town.

The main characters are Molly Barnes (whose mother runs a guest-house) and her best friend Abigail Murfitt (who lives in a house by the railway and whose mother opens and closes the level-crossing gates). In the first story, a London evacuee called Adam Swales comes to live with Molly, and all three of them become friends as the stories progress.

Other children come into the stories from time to time, but Molly, Abigail and Adam are in all of them. You can see them on all the book covers.

Paradise Barn itself stands in open country at the edge of the town. The three children spend a lot of time there and – with the permission of the farmer who owns it – they have a private den in a secret room there.

Great Deeping resembles Littleport, where I spent my childhood. But it isn’t exactly the same as Littleport. It is its own place, where anything can happen.