Sherlock Holmes and the Secret Weapon

The fourth of Universal's Sherlock Holmes films updates Arthur Conan Doyle's "The Adventure of the Dancing Men" to wartime. Holmes smuggles a Swiss scientist out of Zurich ahead of the Gestapo and brings him to London, where the man has developed a revolutionary bombsight he intends to give the Allies. When the scientist is kidnapped, Holmes and Watson discover that Professor Moriarty is behind it, working to deliver the weapon to Nazi Germany. Basil Rathbone and Nigel Bruce are in their familiar roles, with Lionel Atwill as a silkily malevolent Moriarty. The film grafts a spy thriller onto a Conan Doyle puzzle and was made on a small budget at a moment when the series leaned hard into the war effort. It was released in 1943 and is in the public domain in the United States.