Francesca Simon was born in the United States and attended both Yale and Oxford universities. For ten years she worked as a freelance journalist. She now writes fulltime and has had many books published including the bestselling Horrid Henry series and several picture books. She lives in North London, England, with her husband, Martin, and her son, Josh.

Tony Ross is a prolific illustrator of books for children, including Francesca Simon's Horrid Henry series, Martyn Beardsley's Sir Gadabout stories - as well, of course, as his own stories. Over the past few years, Tony has become one of the best known creators of original and traditional picture books and his work has been sold all over the world. Tony Ross was born on August 10, 1938, in London. He trained at the Liverpool School of Art and has worked as a cartoonist, a graphic designer, as the Art Director of an advertising agency, filmmaker, and as Senior Lecturer in Art at Manchester Polytechnic.