Celebrity Personal Assistant
You'll be all around it, but unless you push your boss out of the way of a moving train (or into it), you will be shrouded in relative obscurity. It is not your job to be famous, but rather to blend in behind the scenes like a perfectly healthy thumb, and give your celeb room to breathe, thrive, and shine.
Of course, if this is just something to do on the way to becoming an actor yourself (and this may not be the best way to stick your foot in the door), then best of luck to you. Hopefully some day you, too, will be able to torment and torture a prisoner of your own.