Startling that no one has yet even mentioned his turn in 1988's The Adventures of Baron Munchausen, containing as it does a scene that might persuade you he was one of us, though with his Oscar-winning acting talents I suppose he could have portrayed any kind of deviancy effectively. Still..."pillow-biter," anyone?
To wit (please be gentle with me, this is my first attempt at embedding a video here, I just hope I don't screw the pooch):
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