Yikes. I don't think it's Dirty Harry. Don't know why just a hunch. The Joker is very quiet these days too as is the Sundance Kid. One person worries me is Henry Jones Jr. His public appearances of late have been rather odd and he's certainly busy making films at the moment having been in semi-retirement. Only thing is he hasn't won an Oscar. But he HAS been nominated. Hard to believe this is anyone under 60s if they think it's probably Alzheimer's.
How about the original Green Goblin?