"Supergirl's" Harewood On Martian Manhunter's Tragic Origin, the White Martian Threat

"Supergirl's" Kara Danvers isn't the only individual concealing a secret identity. As viewers discovered early on in Season 1, DEO head Hank Henshaw is actually J'onn J'onzz, better known to comic book aficionados as the shapeshifting Martian Manhunter.

Thus far, details concerning J'onn's home planet and private life have been scarce, but that's about to change. The White Martians, a savage alien race that wiped out Mars' entire Green Martian population, have arrived on Earth in order to deliver the finishing blow to Mars' last remaining survivor.

RELATED: "Supergirl" Director Says Martian Manhunter Episode Will Make You Cry

Ahead of tonight's episode, "Strange Visitor From Another Planet," actor David Harewood spoke with CBR about bringing his character to life and delving into J'onn J'onzz's origins. We talked about introducing his comic book counterpart's weakness to fire to television, the danger of dealing with rampaging aliens and the tease of even more invaders from other planets as Season 1 rolls on.

CBR News: I know you were as shocked as anybody to learn that your character, Hank Henshaw, was the Martian Manhunter. What surprised you most about the character once you started doing research on him?

David Harewood: Just the depth of his story, the depth of his suffering and the amazing mythology that's behind him. There's the fact that I really had no idea that he even existed. I was a Stan Lee guy as a kid. I read a lot of Marvel, like "The Incredible Hulk" and "Fantastic Four." I wasn't aware of the Martian Manhunter as a character. I was staggered by the range of his powers and his story. What a brilliant story, that he was transported here and then basically left alone to learn Earth's ways from the television and what he saw around him. His whole story was a revelation to me.

Tonight's episode, "Strange Visitors from Another Planet," delves into J'onn J'onzz's backstory. How much are we going to learn about him?

One of the brilliant things about the show is that they introduce DC characters and lore, but put a fresh spin on it. What we do is talk about how Hank ended up being the Last Son of Mars. We touch upon how he got there, what happened to his family, what happened to his daughters. It's quite moving, and I think how we do it will hopefully make quite an impact.

The White Martians wiped out J'onn's entire race. What are they doing on Earth, now?

Whenever J'onn uses his powers, because they are a member of the same race, they know when each other are around. The White Martians pick up that J'onn is using his powers and hone in on him. They want to get rid of him.

The White Martian is a completely CG character, but so is the Martian Manhunter. How much of this role is you interacting and fighting with thin air?

It's a little bit of both. We're finding our feet and finding our way with the amount of digital and the amount of real life stuff that we can do. The show's creators are keen to show J'onn as much as we can, but also to show me as much as we can. Obviously, I can play the more nuanced scenes; it's better to have the actor than the CG model. Throughout the fights, you will get to see if people can tell which is CG and which is real life.

What was your impression of the White Martian's appearance?

It was incredible. It was a huge, frightening and terrifying being. While I was researching, I was wondering, "J'onn is a pretty big guy himself and can look after himself. The White Martians must be bigger and badder if they were responsible for wiping out a whole race of green Martians." What we show in the footage and the flashbacks is that they are a pretty formidable species.

Does this episode explore J'onn's weakness to fire?

Yes, and this won't be the last time. We really do tell the history. We try and put a spin on it, but we do try and give as much as we can to the attributes and characteristics of the comic book lore.

So far, Hank has come across as composed, stoic and guarded. How pleased were you to show another side of him?

I was delighted to show another side of Hank. I was getting mauled on Twitter. Everybody hated me at first. They were thinking I was the bad guy. Obviously, I knew all the time that things were going to change. Now, people are seeing this huge depth to Hank and huge depth to J'onn. It's fun to play all these different levels.

I think it's a very emotionally-charged episode. We filmed this just around the time of those awful Paris attacks, and you couldn't help but let your mind wander about the craziness that we experience as human beings, and that we do our best to kill each other every day. Those were the emotions that were bubbling underneath when I was playing those scenes, just how tragic it is that we continue to kill each other. That, for me, was the underlying emotion I was concentrating on throughout this whole filming.

At this point, National City already fears aliens. With that in play, will there be any fallout from this episode?

Without a doubt. We always knew we wanted to get the first seven or eight episodes out of the way, because there was so much more to come. We are really excited for the audience to see where we are taking the story. There's going to be another rampaging alien that terrifies people at some point, and you might be surprised to find out who that is.

The audience is really going to enjoy Hank's storyline. Hank has spent a lot of time keeping his identity secret. It's going to be a battle to see if he can continue to do so. I can tease that might not be the case.

Tom King's Batman Isn't Done With 'The Button' Yet

More in Comics