I grew up watching the Hammer horror films on TV in the late 1970s. Even though some of them were severely edited (for violence and time) they still scared me silly and I was impressed by the acting and lush settings. In 1994 (a few years before Peter Cushing's death) they got together him and Christopher Lee to narrate a documentary on Hammer films. They also had tons of interview footage of Hammer directors, producers, editors, composers, executives etc etc talking about productions. Also many actors of the various Hammer movies talked about their roles and the productions themselves. Raquel Welch and Martine Beswick give very amusing commentaries and Veronica Carlson talks about a disgusting rape scene she was forced to act in for "Frankenstein Must Be Destroyed". It was (thankfully) cut from the final print but the footage is here.
If you're a horror fan (like me) this is a just engrossing insight into how some of the best horror films of the 1950s-1970s were made. This isn't a whitewash job either. The actors and executives do complain about issues and problems they had with scripts and productions. Just fascinating from beginning to end. My only complaint--the footage from Hammer films is in pretty poor shape. Couldn't they have gotten some better prints?