When Star Wars: The Force Awakens opened in theaters in December of 2015, it broke almost every box-office record on the books. It had the biggest Thursday preview in history. It had the biggest Friday in history. It had the biggest single-day gross in history. It was the first film to gross more than $100 million in a single day. It was the fastest film in history to $100 million and $200 million. It was — and remains, even after Avengers: Endgamethe top-grossing movie in U.S. history. In this one writer’s purely subjective opinion, it did reasonably okay in theaters.

The Star Wars prequels were hugely successful, but their ticket sales weren’t in the same league as The Force Awakens, in large part because it had something the prequels never did: The returning cast from the original Star Wars trilogy. Fans were intensely curious to see what the old heroes were up to 30 years later — and to see what they looked like decades after Return of the Jedi. They found a Han Solo who’d gone gray, but still maintained his closet of space rogue fashions. Princess Leia was now a regal general of the Resistance. And Luke Skywalker had grown a hermit’s beard and long hair while living in isolation on a distant planet.

Even though robots don’t age, some of the franchise’s familiar droids looked different too. Cowardly, bumbling C-3PO spent The Force Awakens doddering around with a red arm. No explanation was provided for the arm swap — you had to read a Marvel comic book for that — nor was an explanation given for why he was back to his more familiar gold in the film’s final scene.

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Some fans got upset about the seemingly pointless change; I joked in my 2015 review of The Force Awakens that Disney slapped that red arm on Threepio so they could sell “two C-3PO toys; one with a gold arm and one with a red arm.” And that surely didn’t hurt. But I have to admit I did not realize in 2015 — or at any point in my nearly 40 years on this planet — that a precedent existed for C-3PO’s appendage adjustment. Unbeknownst to me and to many people I’ve consulted since I made this discovery, C-3PO had a mismatched limb through the entire original Star Wars trilogy.

C-3PO has a silver leg — the right one, below the shin.

The silver leg is visible in C-3PO’s very first appearance in Star Wars. The first time Threepio appears in A New Hope, the silver leg is onscreen:

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He keeps the silver leg all through A New Hope and still has it in The Empire Strikes Back. It’s particularly visible in the Rebels’ Echo Base on the ice planet Hoth. (This shot is zoomed in so you can see it a little more clearly; all these screengrabs were taken from the current prints on Disney+.)

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And Return of the Jedi? Silver leg city:

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C-3PO even made publicity appearances with his silver leg. Here he is at the premire of the Star Wars Special Edition in 1997.

Ron Galella Collection via Getty

Although randomly swapping out a character’s gold leg for a silver one 15 years later sounds like something George Lucas would have done, this is not a recent change made to Star Wars. C-3PO had a silver leg back in 1977. Just ask the man who plays him, Anthony Daniels. In this recent video for Wired, Daniels talks about how the C-3PO costume evolved, and how the silver leg was part of the design from the beginning. The intent, he explains, was to show that C-3PO had a history long before the particular adventure in A New Hope. At some point along the way — like the red arm, it’s never explained — he lost his original right leg and settled for this imperfect replacement:

As Daniels notes, even Star Wars’ onset photographer didn’t notice his one silver leg for weeks into production. On or off the set, the silver leg seems to reflect whatever is around it — including the gold from the other leg and the rest of the C-3PO costume. Plus, C-3PO spends a lot of time  wandering the desserts of Tatooine, whose light brown sands make the silver leg almost impossible to spot, as in this shot:

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There are a few other reasons C-3PO’s silver leg is so obscure that some writers have attributed their personal discovery of it to the Mandela Effect. For one thing, it’s only the lower part of the leg that’s silver — and there’s not that many full-body shots of Threepio in the movies. He’s usually filmed from the waist up, like in the Rebel base at the end of A New Hope.

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He’s also typically flanked by R2-D2, and he tends to block C-3PO’s legs, like it in this shot from Return of the Jedi.

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It’s also worth mentioning that most of the adults discovering Threepio’s silver leg today were probably watching this movie at home on VHS — whose resolution pales in comparison to modern technology like Blu-rays and high-definition streaming. My childhood copies of Star Wars weren’t even commercial VHS tapes — they were homemade dubs recorded from television, rendering them even blurrier. I was lucky I could see C-3PO at all, much less make out the fine details like a vaguely silver leg.

Just look at this vintage Kenner Star Wars toy commercial featuring C-3PO and R2-D2. Is Threepio’s leg silver here? Maybe! It’s impossible to tell at this resolution.

That brings up another reason — maybe the single biggest reason — this whole silver leg thing comes as a shock to me and to many people: The Kenner toys, both in 1977 when the original films were released, and the Power of the Force toys that appeared in stores in the 1990s in the run-up to the movies’ Special Editions, had two gold legs.

Kenner

Kids might have watched the movies a dozen times — but they played with these action figures hundreds of times through the years. And the toys had gold legs. When I close my eyes, that little plastic guy on the left is the first thing that comes to mind when I think of C-3PO. My personal toy was a little duller because of all the attention he got from me and my brother — but he was still all gold.

But what about you? Did you always know C-3PO had two different color legs? Did you learn it recently, say when the Star Wars movies premiered on Blu-ray? Or are you just hearing it from me for the very first time? Be honest, there’s no shame here.

Whatever you thought before, now you know conclusively. Before he had a red arm, C-3PO had a silver leg. And now that you’ve seen it, you’ll never not see it.

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