Sir Christopher Lee--A Remarkable Life

Well, holy crud.  In his youth, the man who played Saruman, Count Dooku, Dracula, Sherlock Holmes, and the head of a murderous occultic cult, among a lot of other parts, fought Nazis.  Indeed, he fought Nazis to such a degree that he has expert knowledge of what the sound of someone getting knifed in the back should be.

And behold--he also has enough first-hand experience of black magic and the occult to pass along this sage advice:

I warn all of you: never, never, never. You'll not only lose your mind, you'll lose your soul.