Fans of the galaxy’s greatest protocol droid have noticed that in Star Wars: The Force Awakens, C-3PO has a new red arm. In a special one-shot from Marvel, we’ll learn just how and why he got it.

Today, Marvel announced Star Wars Special: C-3P0 #1, a new story from the Journey to Star Wars: The Force Awakens publishing program coming in December. Reuniting the acclaimed and award-winning writer and artist team of James Robinson and Tony Harris for the first time in nearly two decades, the tale follows “golden rod” on a solo adventure leading up to his appearance in Star Wars: The Force Awakens — and reveals what led to this change in appearance.

“That’s a really exciting part of doing this story,” says Robinson. “I saw a photo of C-3PO with his red arm the other day and I thought ‘Wow, I’m the writer who gets to explain that.’”

You may not be fluent in over six million forms of communication…but this book is a must have in any language.

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