Ariadne Oliver is a successful detective novelist that appears in two short stories (with Parker Pyne in Parker Pyne Investigates) and seven novels (six of them with Hercule Poirot). Played by the brilliant Zoe Wanamaker
Agatha Christie - The world's best-known mystery writer. Agatha Chrisite's books have sold over a billion copies in the English language and another billion in over 45 foreign languages. She is outsold only by the Bible and Shakespeare.