Actually the true reason that Christopher played Saruman and not Gandalf (and I have heard him talk about this many times) was because they both agreed that he was too old, and that they needed a younger actor to play a character who is so incredibly active. Christopher Lee is actually 82 years old, and Ian is in his sixties. Mr. Lee would have most definitely have played Gandalf if the film would have been made years earlier. Though I don't think that Tolkien would have had a problem with the amazing performance that Sir Ian gave (In my opinion he didn't just play Gandalf, he became Gandalf
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