Before Anakin turns to the dark side and Order 66 gets dished out, Senator Palpatine keeps his secret identity of Darth Sidious under wraps for some time, even managing to keep his eye color his own. This is because Sidious has become such a master of the dark side that he can refrain from giving away which camp he is in to benefit his evil plans. It is only at the end of “Star Wars: Episode III – Revenge of the Sith” that he fully embraces his true calling and all the perks that come with it, demonic eye color included.
In the case of Count Dooku (Christopher Lee), however, it isn’t a matter of hiding his influence from the Sith but being motivated for more personal reasons. Dooku isn’t so devoted to Sith ideals but sways to their tactics after coming to believe the Jedi have gone off track from what he initially signed up for. As a result, the dark side is a means to an end and not the be-all and end-all for Dooku in his eyes, which is quite literally why he doesn’t share the same evil ocular trait that the other Sith member has. In the end, the more filled with rage a Sith is, the higher the level of infuriated eyeball on display to match their unbridled anger.
To learn more about the dark side’s power, check out the most powerful Sith in the “Star Wars” universe.
