Dame Agatha Christie (1890–1976) was a British crime writer best known for her detective novels and short stories. According to Guinness World Records, she is the bestselling novelist of all time, her novels having sold over two billion copies and having been translated into more than one hundred languages. The Agatha Award for best mystery and crime writers was named in her honor.

Charles Armstrong is a narrator and actor whose theater work includes productions for the Royal Shakespeare Company and the National Theatre, and he was in the West End production of Round The Horne … Revisited. His television and film credits include Holby City, EastEnders, Head Over Heels, Poirot, The King’s Speech, and The Navigators. He has also recorded numerous voice-overs and was part of the BBC Radio Repertory.