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In the photo, seen below, Downey Jr. can be seen wearing a shirt with a round hole in the middle. It didn’t take long for people to notice it and put two and two together: It’s the exact shape of an arc reactor, the electromagnet Tony Stark surgically embedded in his chest to keep him alive. The vibrant blue piece of technology, which also sits at the heart of the Iron Man costume, defined the superhero’s look … until the end of Iron Man 3, when Stark figured out a way to safely remove the shrapnel that had been embedded in his chest since an explosion in the first movie.

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