A lot of thought went into building the background of Rogue One — despite the fact that it itself is derived from one line of backstory that came from another, previous movie. The movie introduced audiences to entirely new planets, characters, and spaceships, as well as a friendly new droid that quickly became a fan-favorite due to his dry, sarcastic humor. Alan Tudyk, who voices K-2SO, and Animation Supervisor Hal Hickel recently revealed what went into building the droid’s backstory.

Speaking with Comicbook.com, Tudyk and Hickel explained that before K-2SO was captured by the Rebellion and reprogrammed, he was an Imperial drone, “scurrying around” and following orders.

The backstory was pretty limited. Knowing that he was in the Empire, he was sort of reborn when Cassian gave him his reprogramming. He was enslaved, in a way. He was more of a stoic character. He had to follow orders. Basically, he just scurried around. He did lots of security stuff. He had a big bunch of keys that hung off his belt.

K-2SO, despite being just one in a line of identical robots, has a distinctly roughed-up look. He’s a little dinged up from his time with the Rebels and away from any kind of Imperial Jiffy Lube garage where he could be fixed up.

You glimpse another enforcer droid in the Imperial facility and we had him look really spotless. No paint chips or anything, whereas K-2 is all scratched up. We actually considered whether they [the Rebels] might even completely remove the Imperial insignia on his shoulder. We decided to keep it, it’s kind of scratched up, but you can still see it. We figured the Rebels are kind of rough and tumble and they’re not going to be too precious about it. But we did give it lots of history, scratches and dents, to really communicate that he had seen a lot of action with Cassian.

I like that detail about how they decided to keep the insignia — and it certainly helped when they used K-2SO to sneak into that Imperial base.

Rogue One is now out on Blu-ray and digital.

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