Michael J. Fox has been fighting Parkinson's disease for over two decades now!!
He's being fighting it inside his own body as well as through his charity, The Michael J. Fox Foundation.
Recently, the acting bug has been creeping up on him, and he's been increasing his number of cameo roles on shows like The Good Wife and Curb Your Enthusiasm.
He went on Letterman to discuss the new show and talk about how much it will mirror his own life.
Michael seems really happy to be getting back into TV and we're glad to know he's healthy enough to do it!
Check out the video (above) to see his hilarious Letterman interview!