Sir Christopher Lee reported to work on this movie after a vacation in Northern Italy with a deep tan, which was problematic for the Make-up Department, as his character was supposed to have very pale skin.
Sir Christopher Lee said in interviews that the make-up he sported in this movie to transform him into a Chinese man was the most uncomfortable make-up that he had to endure at that point in time.
Shot in the months of April and May 1960.