Star Wars' Darth Vader was responsible for giving us Christopher Reeve's iconic depiction of Superman. Well, in terms of physique at least.

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In an interview from The Hollywood Reporter's archives, the man who was under the Darth Vader costume, David Prowse, revealed that Superman director Richard Donner left him in charge of bulking up a scrawny Reeve for the 1978 movie. Donner labeled Reeve, at the time 6 feet, 5 inches and 170 pounds, a "skinny little kid" and proceed to enlist the help of Prowse, who appeared as the towering Vader just a year before in Star Wars: A New Hope.

"I get a call from Dick Donner and he says, 'Can you get down to the studio as quick as you can, we've got a Superman,'" Prowse, who was also a bodybuilder and weight-training instructor, said. "He was fantastic. He was a very lovely person. We were like brothers, we got along so well together. And during the course of the period I had him, I took him from 170 pounds when we started and he was 212 [pounds] when he went into the suit."

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Under Prowse's daily guidance, Reeve ate four meals while on a high protein diet with vitamins, en route to becoming the Man of Steel and what many deem the quintessential representation of Superman onscreen.