How many novels did the detective who helped Antoinette Marceau on the Murder on the Orient Express appear in?
Hercule Poirot Hercule Poirot ( ; ] ) is a fictional Belgian detective, created by Agatha Christie. Poirot is one of Christie's most famous and long-lived characters, appearing in 33 novels, one play ("Black Coffee"), and more than 50 short stories published between 1920 and 1975.
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.