Emperor Palpatine is the only villain to appear in each of the "Star Wars" trilogies, threatening the Skywalker family and the galaxy. Despite his importance as a looming figure over the entire franchise, the antagonist was eventually recast, leading to one of the most iconic performances in pop culture.
In "The Empire Strikes Back," Palpatine briefly appears as a hologram and is played by female character actor Marjorie Eaton, with the voice of actor Clive Revill. After it was decided that Palpatine would be a significant force in the franchise moving forward, it became clear that the character couldn't be concealed using a hologram.
Alan Webb was chosen to portray Palpatine but had to pass after falling ill, which led to Ian McDiarmid portraying the villain. McDiarmid starred in each of the trilogies, including 2019's "The Rise of Skywalker," which was unexpected, considering Palpatine was supposed to be dead.