Paul Dehn was the screenwriter for which 1974 British mystery?
Murder on the Orient Express (1974 film) Murder on the Orient Express is a 1974 British mystery film directed by Sidney Lumet, produced by John Brabourne and Richard B. Goodwin, and based on the 1934 novel of the same name by Agatha Christie.
The Unicorn Murders The Unicorn Murders is a mystery novel by the American writer John Dickson Carr (1906–1977), who published it under the name of Carter Dickson. It is a locked room mystery (more precisely, it is a subset of that group, an impossible mystery) and features his series detective, Sir Henry Merrivale.