Robots and science fiction have always gone hand-in-hand in film, putting man's fascination with giving life to machines on full display. The Star Wars franchise has embraced automaton assistants regularly, introducing audiences to a wide variety of androids capable of awesome abilities. Of the series' most memorable robots, C-3PO stands out as one of the most iconic, having been featured in all eight films. When speaking at a panel at Star Wars Celebration, George Lucas himself revealed the key component to making the droid so memorable, which involved some assistance from Anthony Daniels.

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During a panel that celebrated the original film's 40th anniversary, moderator Warwick Davis, star Anthony Daniels, and creator George Lucas all began debating the process of creating C-3PO, with Lucas chiming in as the ultimate authority of what made C-3PO so iconic. "The key to the construction of you was the face. The face had to be absolutely neutral so that you could act, and your acting would come through and it wouldn't be counter to what your face was doing," Lucas revealed.

Daniels jokingly griped about how he had to strip his clothing so plaster casts could be made of his body to help design the suit to fit him perfectly, but he didn't seem to mind George's thoughts. Lucas explained, "So by having your face fully neutral, everything you did, and your movements, which was hired I mimed, was because the acting was in the physicality of it. It was very hard to come up with a face that was completely neutral."