Darth Vader is talking to the Emperor via a holographic image in the first episode of the original trilogy. That emperor is supposed to Palpatine, who we learn much more about in the other films. However, at the time, the actual actor (or should I say actress) that played the Emperor was the wife of Rick Baker (famed monster creator). Like Vader, she played the body and face of the holographic image, but Clive Revell played the voice. In watching the films now, I don't know if I would have even noticed the difference.