Sherlock Holmes - Terror By Night/Dressed To Kill

SHERLOCK HOLMES IN TERROR BY NIGHT (1946):

Holmes is hired by Lady Margaret Carstairs to prevent the theft of the Star of Rhodesia, a priceless diamond, as it is transported to Scotland aboard the London to Edinburgh Express, En route, Lady Carstair's son is murdered and the diamond is stolen and everyone on board has their own secret agenda. The master detective must use all his powers of deduction to recover the jewel and bring the murderer to justice.

SHERLOCK HOLMES IN DRESSED TO KILL (1946):

In the last film of the Rathbone series, an innocent hobby turns deadly when a collector is murdered for a secret contained in a music box. Unbeknownst to the unlucky collector, the music box holds part of the key to the location of five-pound note printing plates stolen from the Bank of England.