Dr. Who is an extremely long running, at times superb Sci Fi series from the UK. There have been multiple actors in the role (at least half a dozen), they work around this by having the character morph into a new person when it regenerates. The version I am most familar with, and watched weekly growing up, was portrayed by Tom Baker. There is a new incarnation of the series coming to the Sci Fi channel in March. I'll give it a chance and see how it goes.