This last appearance for the detective team was genuinely pleasing, as they attempt to solve the puzzling killing of a man named "Stinky" (Edmund Breon), who happened to have attended school with “Dr. Watson.” His violent death seems impossible to understand, except for the theft of an unremarkable music box from his house—a box crafted at Dartmoor prison. The inquiry then uncovers that these boxes were produced by a convict holding onto a significant piece of information, something "Mrs. Hilda Courtney" (Patricia Morison), who favors perique cigarettes, and her associate "Hamid" (Harry Cording) are determined to obtain, regardless of the cost. As is often the case in these stories, Nigel Bruce ("Watson") once more manages to be the most memorable character and ultimately resolves things—and alongside Basil Rathbone, they conclude this series with a positive feeling. PS: What was Dr. Samuel Johnson’s cause of death...?

Source on TMDB