Anthony Joshua Shaffer (15 May 1926 – 6 November 2001) was an English playwright, screenwriter, novelist, barrister, and advertising executive. He is best remembered for his Tony Award winning play Sleuth (1970) and its acclaimed 1972 film adaptation. His screenplays included Alfred Hitchcock's thriller Frenzy (1972) and the folk horror film The Wicker Man (1973). (Via Wikipedia)