Doyle set to launch his first children's book

Roddy Doyle, the Booker prize-winning author best known for his gritty portrayals of working-class life in Dublin, is to take on Harry Potter, with his first children's book.

The bestselling author of The Commitments and The Woman Who Walked Into Doors has written about subversive imaginary creatures in The Giggler Treatment. Chiefly directed at eight year olds, the book will be published in September. Scholastic Children's Books, the publisher, will launch the book simultaneously in the UK and United States amid a major publicity campaign, and industry sources expect it to be a bestseller.

The Giggler Treatment centres on the eponymous Gigglers, imaginary characters who seek revenge on adults who are overly stern with children. "They do things like making [the adults] step in dog poo. It's good, irreverent Roddy Doyle stuff," a source said. The subject could not be further from Doyle's last best-selling book, A Star Called Henry, which examines modern-day Irish nationalism.

Scholastic is expected to make a formal announcement about the new book within the next few days. The publisher, not known for its Booker prize-winning authors, is understood to be jubilant about what it considers a literary coup. It has already advertising the book at this week's London Book Fair, where publication rights are bought and sold.

Children's fiction can be a lucrative literary genre - as JK Rowling, author of the Harry Potter series, has manifestly discovered. But Mr Doyle will not be playing a major part in publicising the book as he is "too busy" with other projects, including a forthcoming film adaptation of his screenplay for the romantic comedy When Brendan Met Trudy.

His ongoing projects do not, however, include a script for the sequel to the 1991 hit film The Commitments, based on his book about a Dublin soul band.