A real old time actors film if ever there was one. Peter Cushing in his 70's plays Sherlock Holmes for the last time. He had played Holmes in Hammer's good version of The Hound of the Baskervilles and in a TV series. British actor John Mills was Dr. Watson. Mills was I believe 76 years old when this was filmed. The rest of the cast is virtually a list of old guy British actors, Ray Milland, Gordon Jackson, Anton Diffring and somewhat incongruously American actress Anne Baxter in the role of Irene Adler.
The plot has Holmes and Watson called out of retirement to find a missing German prince. But what you really have in this film is a couple of very good veteran actors showing how it's done when it comes to performing. The film was directed by another old veteran Roy Ward Baker whose career started in 1947 and lasted until 1984. Cushing had worked with Baker at Hammer so they probably got along very well.
The Masks of Death is Cushing's last major role before his retirement. He did some minor work after that but his health had started to decline. Peter Cushing certainly had an interesting career. His work at Hammer studios left an indelible mark on the studio and he found a whole new fame as Grand Moff Tarkin when George Lucas cleverly cast him in Star Wars. A remarkable career.
The film was written by Anthony Hinds and N. J. Crisp. The running time is 78 minutes.