Ian McDiarmid as Palpatine
Movies - TV
Why The Emperor’s Force Lightning In Star Wars Didn’t Scar Luke Skywalker
The climax of "Return of the Jedi" involves Palpatine torturing Luke with lightning for a significant period, yet Luke recovers from it all unscathed.
If Palpatine developed heavy facial wrinkles in "Revenge of the Sith" when the same thing happened to him, it doesn't seem to make sense that lightning doesn't scar Luke.
Ian McDiarmid, who played Palpatine in all three trilogies, shed some light on the issue in a 2016 con panel. He shared the direction he received from George Lucas.
McDiarmid explained, "He said, 'You should think of your face, i.e. Ian's face, the one you can see as the Senator and the Chancellor more or less, as a mask."
Lucas told McDiarmid that underneath the mask is the reality of the character. In other words, Palpatine's face was never fully real, so the Force lightning could scar it.
McDiarmid said his theory was helpful — and it's why you should always make absolutely sure someone's a secret Sith before blasting lightning to reveal their true appearance.