Funnyman David Walliams has announced the name of his new children’s novel as Grandpa’s Great Escape.

The Britain’s Got Talent judge described his latest book as a “funny and moving tale of adventure”.

HarperCollins said it will take readers on a journey with Spitfires over London and great escapes through the city in a high-octane adventure.

Speaking about the book, David said: “Grandpa becomes muddled in his old age, he believes he is back in World War Two when he was a RAF fighter pilot.

“When he is sent to an old folks’ home, he is convinced it is a prisoner of war camp. Together with his grandson Jack, he plans a daring escape. I hope my young readers will love this funny and moving tale of adventure.”

Its front cover, tweeted by the comedian, features a drawing of an elderly man and little boy flying a plane.

Tony Ross, who has worked with David on five of his seven previous fiction titles and all three of his picture books, will illustrate the book.

HarperCollins children’s books executive publisher Ann-Janine Murtagh said: “I’ve published David Walliams for seven years and each time he delivers a new book, he enthrals and enchants me.

“And when Grandpa’s Great Escape arrived, I was completely blown away. This is tender-hearted storytelling with the boldest and most audacious of his adventures yet.

“It’s a story that steals your heart in the way that only David Walliams can. Millions of children across the globe are waiting for Walliams’s next book – and there’s a good reason: David is simply an incredible storyteller with an extraordinary imagination that always surprises.

David Walliams
David Walliams (Lionel Cironneau/AP)

“Grandpa’s Great Escape is set to be the biggest book next year by the best children’s storyteller in the world.”

David, who stars in BBC’s drama Partners In Crime, has sold more than 7.5 million books in the UK, and his most recent fiction title, Awful Auntie, published in September 2014, went straight to number one in the children’s book chart and remained there for seven weeks, returning to the top of the children’s charts for the coveted Christmas number one slot.

Awful Auntie has now sold more than 657,000 copies and was the biggest selling book, across all categories, published in 2014.

Last year, the 43-year-old funnyman generated upwards of £7 million for sales of his top children’s books, making him one of the biggest stars of the literary world.

And his golden touch for children’s titles saw him take four places in the top 50 bestsellers across all genres in the 12-month period, according to figures published in trade magazine The Bookseller in January.

Together, the books – which also included Gangsta Granny, Ratburger and Billionaire Boy, each published by HarperCollins – had a retail value of £7,060,788.

In the July 10 edition of The Bookseller, the magazine reported that he has had year-on-year growth of +30.9 percent.

His sales are further buoyed by TV adaptations of his books by the BBC. The Boy In The Dress was shown in the Christmas schedules with a starry cast which included Jennifer Saunders, Meera Syal and David himself.

Grandpa’s Great Escape will be released on September 24.