After the King of Ruthenia has been assassinated, Holmes and Watson are engaged to escort his son to Europe via Algiers, aboard a transatlantic ocean liner which also carries a number of suspicious persons, any of whom may be involved in a plot to also assassinate him.

Mystery, Crime, Thriller

Basil Rathbone, Nigel Bruce, Marjorie Riordan, Rosalind Ivan, Morton Lowry, Leslie Vincent