TV URBAN LEGEND: Martian Manhunter got his start on Supergirl due to a joke.
When Hank Henshaw debuted on Supergirl as the head of the Department of Extranormal Operations (DEO), he was a bit of a jerk who REALLY didn't like aliens.
That was actually in keeping with the comic book version of Hank Henshaw, who was a total jerk who became a cyborg version of Superman (granted, that version of Hank Henshaw was white, but otherwise, same basic idea - total jerk).
However, it was then revealed that Hank's whole anti-alien persona was actually a COVER for his REAL identity, which was the alien known as J'onn J'onnz, better known as the Martian Manhunter!
He has become one of Supergirl's greatest allies on the series.
Amusingly enough, though, when the show began, Henshaw was NOT going to be the Martian Manhunter. He was likely hiding an ACTUAL dark secret, rather than a surprisingly HAPPY secret. I say "amusingly" because the change to the plot happened because, of all things, a joke between writers on the show!
Former Supergirl executive producer Andrew Kreisberg explained it to the Hollywood Reporter:
"[DC Comics CCO] Geoff Johns, [executive producer] Greg Berlanti and I were saying, 'It's so funny we cast David because he's got those weird ears. Like alien ears,' " Kreisberg says. "I don't remember which one of us said it, but it was like, 'If we were ever going to make a Martian Manhunter show, David would have been the perfect Martian Manhunter.' And Geoff said, 'Well, why can't he be?' We already had it set up that Hank was keeping this bad secret, and then we started thinking about well, what if it was a good secret? You think he's bad but then he turns out to be not only good, but the most good person in the DC universe."
Harewood himself did not know about the change into about two weeks into the gig, noting:
I was told about two weeks into the job. I knew something was changing [during the pilot], but I wasn’t absolutely sure what it was. Part of it was quite uncomfortable because a lot of what Hank said was exposition and was, “D.E.O., I’m this, I’m here.”
I was really pleased—Martian Manhunter is such a huge character. It took me in a new, different direction, and it was brilliant for me because as much as I could, I couldn’t really find an angle to play Hank Henshaw [prior to then]. It was interesting.
Of course, at first Harewood was freaked out, noting, "Andrew gave me this model of a green Martian, and at first, I was a bit horrified. I thought, 'I'm going to be playing Shrek for the next seven years.' I was anxious because I could see hours of prosthetic makeup and that was simply not something I wanted to do. But then I started reading it, and I was blown away."
The whole "evil Hank Henshaw" idea, though, got to be recycled by revealing that J'onn took on the form of Hank Henshaw after the original version of Henshaw died. However, he turned out to be alive and he became the Cyborg Superman on Supergirl, as well (well, he became a cyborg at least)...
The legend is...
Thanks to Sydney Bucksbaum for the information!
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