| Complete credited cast: | |||
| Basil Rathbone | ... | Sherlock Holmes | |
| Nigel Bruce | ... | Doctor Watson | |
| Marjorie Lord | ... | Nancy Partridge | |
| Henry Daniell | ... | William Easter | |
| George Zucco | ... | Stanley | |
| John Archer | ... | Lt. Pete Merriam | |
| Gavin Muir | ... | Bart Lang | |
| Edmund MacDonald | ... | Detective Lt. Grogan | |
| Don Terry | ... | Howe | |
| Bradley Page | ... | Cady | |
| Holmes Herbert | ... | Mr. Ahrens | |
| Thurston Hall | ... | Senator Henry Babcock | |
Sherlock Holmes is engaged by the Home Office to locate a British subject traveling for his law firm to Washington, D.C. The man had flown to New York City and then took the train to Washington. On the outskirts of the city, the man was kidnapped and has not been seen for several days now. Holmes learns from the Home Office that the man was in fact a government agent who was delivering a highly secret, two page document to the US government. In verifying the contents at his flat, Holmes concludes the document had been reduced to microfilm. The question becomes whether he may have had the opportunity to pass the microfilm to someone else on the train before he was taken. Written by garykmcd
A British spy carrying important diplomatic papers from Great Britain to the United States is kidnapped. Sherlock Holmes is needed to find the man, and more importantly the papers that would ruin world peace. This is a fine entry into the Sherlock Holmes cycle, albeit a bit thin in the area of plot. Notwithstanding this, Basil Rathbone and the lovable Nigel Bruce make the most of the material and turn the mundane into the sublime. Rathbone is his usual self, however, in this picture he sports a fairly unique hairstyle. Bruce is as ever a fun man to watch, uttering completely comic absurd remarks with the greatest conviction. The supporting cast is first-rate with the indeliable George Zucco as(who else?) the villain. Aiding Zucco is Henry Daniell. Throw in some great character acting by the likes of Gerald Hamer and Clarence Muse. The scene shared by Rathbone and Muse is particularly enjoyable to watch. At the end the film has its wartime message about the importance of democracy. A good mystery!