The Mousetrap' (4 letters) The crossword solutions for the term AGATHA CHRISTIE'S TITLE are DAME and 'The Mousetrap'. Agatha Christie was a prolific English writer of crime fiction and is widely considered to be one of the greatest mystery writers of all time. Her most famous work is the play 'The Mousetrap', which opened in 1952 and has been running continuously since then, making it the longest-running play in the world.