Kitty-in-Boots, unpublished Beatrix Potter story, discovered in author's archive

Peter Rabbit is back, in a previously unpublished story by English children's author Beatrix Potter.

The Tale of Kitty-In-Boots was tracked down by publisher Jo Hanks after she found a reference to the manuscript in an out-of-print book about the author from the 1970s. Potter had written to her publisher about the story of "a well-behaved prim black Kitty cat, who leads rather a double life."

The feline tale also features an older version of Peter Rabbit, the best-known creation of Potter, who died in 1943.

Hanks discovered manuscripts of the story as well as one rough colour sketch of Kitty-in-Boots and a rough pencil drawing of the villain Mr. Tod in the Victoria & Albert Museum's Potter archive. 

• Read an excerpt of The Tale of Kitty-in-Boots

She also found letters that revealed Potter had intended to finish the story, but "interruptions" — from the start of the First World War to farm work to illness to her marriage — eventually got in the way and she never returned to the tale.

"The tale really is the best of Beatrix Potter. It has double identities, colourful villains and a number of favourite characters from other tales (including Mr. Tod, Mrs. Tiggy-Winkle, Ribby and Tabitha Twitchit)," Hanks said in a statement.

I liked the story immediately — it's full of incident and mischief and character... I have a strange feeling that it might have been waiting for me.- Quentin Blake

"Most excitingly, our treasured, mischievous Peter Rabbit makes an appearance — albeit older, slower and portlier!"

Generations of children have grown up with Potter's tales of animal characters including Peter Rabbit, Jemima Puddle-Duck and hedgehog Mrs. Tiggy-Winkle.

Quentin Blake, best known for his work with beloved children's author Roald Dahl, will provide illustrations.

"It seemed almost incredible when, early in 2015, I was sent the manuscript of a story by Beatrix Potter; one which had lain unpublished for a hundred years and which, with the exception of a single drawing, she had never illustrated," Blake said.

"I liked the story immediately — it's full of incident and mischief and character — and I was fascinated to think that I was being asked to draw pictures for it. I have a strange feeling that it might have been waiting for me."

Penguin Random House will publish the tale in September. This year marks the 150th anniversary of Potter's birth.