Francesca Simon spent her childhood on the beach in California and started writing stories at the age of eight. She wrote her first Horrid Henry book in 1994. Horrid Henry has gone on to conquer the globe; his adventures are published in 27 languages and have sold millions of copies worldwide.

Francesca has won the Children's Book of the Year Award and been a judge for the Guardian Children's Fiction Prize and the Roald Dahl Funny Prize. In 2009, in one of the proudest moments of her career, Francesca was awarded a Gold Blue Peter badge.

Francesca is also a passionate ambassador for children's literacy and is a trustee of the World Book Day charity. She lives in North London with her family.

Leo Broadley is an illustrator and lecturer at the University of Derby.

He has written and illustrated a number of books for publishers as well as illustrated for a winery and The Shakespeare Birthplace Trust.