Master sleuth Sherlock Holmes (Basil Rathbone) is hired by the wealthy widow Lady Margaret (Mary Forbes) and her son Roland Carstairs (Geoffrey Steele) to prevent the theft of an enormous diamond known as the "Star of Rhodesia." Traveling by train from London to Edinburgh, Holmes guards the priceless jewel with the help of Dr. Watson (Nigel Bruce) and Inspector Lestrade (Dennis Hoey). But when the diamond disappears and Roland is found murdered, Holmes must deduce the murderer's identity from among the speeding train's many suspicious passengers, including Dr. Watson's old friend Major Duncan-Bleek (Alan Mowbray). Dripping with atmosphere and claustrophobic suspense, TERROR BY NIGHT is a true classic in the pantheon of Sherlock Holmes mysteries.