Happy Birthday Wallace and Gromit. It is hard to believe, but it is 20 years since the Plasticine pair made their debut in 1989's A Grand Day Out. To celebrate the 20th anniversary, publishers Egmont have released a book, The Art of Wallace and Gromit, which features the famous characters in early stages of development. This is an early storyboard for a scene from A Matter of Loaf and Death, in which Gromit and Fluffles unite in their mutual mistrust of Piella. The creator, Nick Park, and his animation studio Aardman, have a month-long exhibition at The Illustration Cupboard in St James's, which opens tomorrow.