Horrid Henry is a nasty boy who thinks only of himself, is beastly to his little brother and dreams of ruling the world from his sofa. If you haven’t got young children, you probably haven’t heard of his exploits. But most parents will recognise Horrid Henry as a byword for naughtiness, greed and mayhem. In fact, Horrid Henry is such a Huge Hit that his creator, Francesca Simon, ranks among the very top children’s authors in book sales.

Some 12m copies of Simon’s titles have been sold in Britain and Henry’s appeal extends to a further 27 countries, including Russia and China. Holding out so far against Henrymania is the US.