She is the biggest selling novelist of all time; only beaten in total by the Bard and the Bible. Her literary style is a byword for veronal in the brandy glass, bodies in the library and grandstanding revelations in country house drawing rooms. She is the creator of Hercule Poirot, Jane Marple, Tommy and Tuppence Beresford, Captain Hastings, Inspector Japp, Superintendant Battle, Ariadne Oliver and countless other sleuths, spies, sidekicks and stooges. She is reknowned for the intricacy of her plotting, the subtlety of her clues, the power of her misdirection. She is, quite simply, the Queen of Crime. But is Agatha Christie actually any good? The American critic and novelist Edmund Wilson certainly didn't think so. His diatribe 'Who Cares Who Killed Roger Ackroyd?' was echoed by Raymond Chandler, purveyor of hard-boiled gumshoe fables and by latter day literary favourites like John Banville. They decry the wooden prose, the stock characters, the relentless formula,