Michael Keaton is Michael Douglas. Michael Douglas is not Michael Keaton. Also, even though Michael Douglas is Michael Douglas, he is not really Michael Douglas. With us?
Michael Douglas (the one not pictured here) was born in 1944 to a Jewish father, actor Kirk Douglas. Of course, as noted previously, Kirk Douglas was really Issur Danielovitch. In childhood, he became Izzy Demsky, and in adulthood adopted the name Kirk Douglas. So Michael Douglas (the one not pictured here) is really Michael Danielovitch.
Michael Douglas (the one pictured to the left) was born in 1951 to a Catholic family. When he made his way to Hollywood, he had to satisfy the Screen Actors Guild rules, which already had the aforementioned Michael Douglas (the one not pictured here). So Michael Douglas (the one pictured to the left) became Michael Keaton.
Still with us? Well, how about this one: the brothers of Michael Douglas (the one pictured to the left) used to, for some reason, call him Jackson. So, before settling on Keaton, he almost became... Michael Jackson.
Michael Jackson (the one not pictured here)...