Dragons the size of a kitten and a house spotted by detective duo at York Theatre Royal

The giant Eragon of York will fly around the Grand Opera House, terrifying Beauty & The Beast audiences from next Friday. Meanwhile, an alarming plague of dragons will swamp the York Theatre Royal Studio from Tuesday. Small ones, tall ones, fiery ones, roary ones, friendly ones, icy ones, scary ones, all rising from the pages of The Book Of Dragons by E. Nesbit.

The Theatre Royal has enjoyed considerable success with Mike Kenny's adaptation of Nesbit's The Railway Children, at the National Railway Museum in York, and later transferred to London and Toronto in Canada, and now associate director Juliet Forster has adapted five of Nesbit's dragon tales for a show suitable for children aged three upwards and their families.

"I'd really loved E Nesbit's Phoenix And The Carpet and Five Children And It and The Story Of The Amulet as a child, though I have to confess I didn't remember that I'd read them! But then I found a copy of The Book Of Dragons – it was my sister's copy – and read them and decided we should do them as our first in-house Christmas show to be produced in the Studio.

"Before now, it's been used as the theatre workshop and for the pantomime, but after the refurbishment and re-design of the theatre, we can now use it during the pantomime season too."

Juliet was drawn to Nesbit's dragons for another reason. "One of the stories is set in Forest Hill, in London, which is where I grew up, and that all came back to me when I read them again," she says. "I remembered the characters, the wit, the craziness of the fantasies, though normally I'd read books again and again as a child – I'd read Jane Eyre seven times by the age of 11; weird child! – but I'd only read The Book Of Dragons once because I'd borrowed it from the library, so the stories must have stayed with me.

“E Nesbit has a really lovely sense of humour and a lot of the dragons in her stories are funny or friendly, not all of them are frightening. Even for someone as young as a three year old, dragons are exciting, magical beings. There are great female protagonists in what are battling dragons kind of stories; there’s a princess who’s really feisty; the dragons are all really different and really interesting."

"It’s a bit like The X Files for dragons,” says The Book Of Dragons director Juliet Forster

This made it difficult to select the five stories to put on stage and so there are elements of the other stories too. Crucially, Juliet's adaptation features a brother and sister, Harry and Effie, one a first-year student at university, the other in the last year of her school studies, who return to their childhood home where they find dragon tracks in the snow.

"I had to find a framing device," says Juliet. "One of the stories, The Deliverers Of Their Country, had these characters, Harry and Effie, who save Britain from a plague of dragons, who come in all shapes and sizes, from kitten size to the size of a living room that eats boys and girls. They're a great pair; they have that old-fashioned word 'pluck' about them, pushing themselves forward to save everyone by going out alone in the middle of the day to solve the problem, whereas everyone else only goes out at night when the dragons are sleeping!"

Hey presto, Juliet had her framing device: the duo of Harry and Effie, a pair of dragon detectives in possession of Harry and Effie’s Book of Dragons, a book full of tales and legends, handed down from long, long ago, as well as really recent eye witness accounts.

In the book are recorded suspected dragon sightings, close encounters of the dragon kind, even dragon conspiracy theories. "So it’s a bit like The X Files for dragons,” says Juliet. “They're the Mulder and Scully of the dragon world, who use their time to find out about dragons and record it all in a book, so they have all the top tips on how to deal with dragons, should you ever run into one."

These investigations started when they were little and so the cast of two, Emilio Iannucci's Harry and Elizabeth Mary-Williams's Effie, play the duo at varying ages, bringing the stories they have gathered to life on stage through physical storytelling, live animation and shadow puppetry.

"Emilio and Elizabeth had both auditioned for my production of E M Forster's The Machine Stops in the Theatre Royal Studio. I remembered Elizabeth had really good movement and was really interesting to watch, and when I was adapting the stories, she kept popping into my head, so I got her to come and read for the role, and she was just fantastic; a really good fit," says Juliet.

"I put Elizabeth together with Emilio at the audition recall to see if they'd work well together and they did. He has a wonderful feel for comedy."

York Theatre Royal presents E. Nesbit’s The Book Of Dragons, York Theatre Royal Studio, December 12 to January 6; suitable for children aged three upwards and their families. Box office: 01904 623568 or at yorktheatreroyal.co.uk