The prompt for thinking about droids right now is not only Baker’s death but also the steadily rising hype for Rogue One, out on December 16. The first in Disney’s one-off Star Wars films that will alternate release years with the franchise’s proper sequels, it tells of the Rebel spies who stole the plans for the Death Star immediately before the events of A New Hope. The full-length trailer that recently premiered during Olympics coverage promises a slick, serious ensemble film with some very cool-looking tweaks of existing Star Wars tropes from Imperial Walkers to desert planets. Perhaps the most intriguing element on display—both familiar and radical within the tradition of Star Wars—is the new droid character, K-2SO.

Visually, K-2SO recalls not his colorful Star Wars predecessors but rather a more archetypical sci-fi robot, gunmetal grey and bipedal, tall enough to make the obvious Iron Giant comparisons relevant. Voiced by Alan Tudyk of Firefly fame, K-2SO tells Rogue One’s protagonist, Jyn Erso (Felicity Jones), “The captain says you are a friend. I will not kill you.” It’s a jarring thing to hear from a Star Wars droid-ally: Can you imagine C-3PO threatening anyone’s life? The filmmakers seem to want us to be drawing such contrasts between the gold-plated protocol droid and this new bot. “There is a 97.6 percent chance of failure,” K-2SO says elsewhere in the trailer, a clear throwback to C-3PO’s pesky tendency of telling Han Solo’s crew their dreadful odds of survival.

The movie’s publicity campaign has given more information about where K-2SO might fit in the droid-hero tradition of the series. (Read no further if you want to avoid knowing anything about the film’s plot outside of what the trailers have shown). As the insignia on K-2SO’s shoulder indicates, he was once Imperial property: a security bot, used as a violent “enforcer.” Rebel pilot Cassian Andor (Diego Luna) reprogrammed him to side against the Empire, but it’s clear he still has dangerous capabilities. Interestingly, EW’s preview of Rogue One says that the droid is “seeking a bit of redemption.”

Even so, it appears he shall continue in the historical droidly role of comic relief. Tudyk has said K-2SO “has no filter... he can say insulting things very casually if he thinks they’re true.” He’s also said, “He’s not an overly emotional guy … He’s not like C-3PO, who’s like a fucking neurotic mess.” The moment in the trailer when he blurts about not killing Jyn confirms that description. This is a darker kind of humor than is typical for Star Wars, but one in line with the grittier tone that’s been promised for Rogue One.

Moreover, the fact that this droid has crossed from working for the Empire to working for the Alliance signals that Disney’s Star Wars are continuing their exploration of moral side-switching. Finn, The Force Awakens’ turncoat stormtrooper, represented the movie series’ first significant glimpse into what life’s like for rank-and-file employees of the Dark Side. Now, both K-2SO and a new character named Bodhi (Riz Ahmed) have gone from working for the Empire to working for its enemies. And the Rogue One trailer promises that much of the movie will revolve around Jyn Erso heading undercover as an Imperial.

Flipping between dark and light is, of course, the foundational conflict of the entire saga, seen in the arc of Anakin Skywalker. It’s possibly much the same conflict that will define the story of Rey and Kylo Ren in the future sequels. From what we know now, K-2SO may not compete with R2-D2 to become the iconic fan-favorite droids of the series, but he will show that the porous boundary between good and evil is one that concerns machines as well as man.

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