[WARNING: This is an article on future Supergirl developments. There will be SPOILERS]

After weeks of speculation of just who from the DC-verse would be making an appearance on CBS’ hit Supergirl, we can finally talk about it. Revealed in the episode “Human for a Day,” a heavy-hitter from the Justice League of America has been hiding out in National City the whole time. Martian Manhunter, aka Hank Henshaw, makes himself known to DEO Agent Alex Danvers – and nothing in National City will be the same.

During a visit to the sets of Supergirl, we got a chance to chat with the cast and creative team behind Supergirl to ask about the process behind bringing Martian Manhunter to the forefront and what that will mean for Kara Danvers and the Supergirl team. Commonly known as the wise voice of the JLA, will the Supergirl version of J’onn J’onzz live up to the role? Here’s what we’ve learned so far.

It Was Always Part of the Plan to Have Martian Manhunter in the Mix

Supergirl Episode 4 Kara Hank Henshaw Supergirl Interview: Hank Henshaws Secret Identity Revealed


As Kara, aka Supergirl, is getting used to the hero life, she’s been running things by trial and error. It would be easy to bring a Superman into the story to show her the ropes, but the showrunners knew early on that there’d be another alien superhero for her to play with. Executive producer Andrew Kreisberg explained the planning for Martian Manhunter started as early as the pilot:

“You start seeing the sets, and you start seeing the actors, and you start thinking about, well, what we could do next and all the different possibilities there could be. It was like, “Oh, if we were ever going to make a Martian Manhunter show or something, David [Harewood] would’ve been the perfect Martian Manhunter.” And it was Geoff [Johns] who said, “Well, why can’t he be?’”  He went on, “We already had the Hank Henshaw idea set up that we would be playing this sort of bad secret that he was holding. Then we started thinking about it. It was like, ‘Oh, well, wait a minute. What if it’s a good secret?’”

Executive producer Ali Adler revealed that knowing the twist has allowed the team to make even smaller moves in anticipation of the reveal:

“We’ve known about this great and amazing piece of Hank for a long time and so it’s really shaped our movements throughout. It’s been nice to have that blueprint in place since we started this.”

Since the role was conceived with a different goal in mind, actor David Harewood got a pleasant surprise, finding out he was actually playing a Justice League superhero in disguise:

“They told me about two weeks into my time here … I knew something was changing, but I wasn’t absolutely sure what it was. I was really pleased—Martian Manhunter is such a huge character. It took me in a whole new, different direction, and it was brilliant for me.”

The Martian Manhunter Backstory will be Explored

Underrated Superheroes Martian Manhunter Deserve Movies Supergirl Interview: Hank Henshaws Secret Identity Revealed


With over 50 years of backstory to play with, the showrunners had to figure out the best way to fit him into the Supergirl storyline. What is known is that J’onn J’onzz is the last of his kind and dealing with the loss of his wife and daughter. If that sounds like some serious story to bite off, it should: it’s also the reason we’ve been hoping (along with DC Comics fans) that a Martian Manhunter movie role was in the works.

A role in the TV series may not be quite as exciting, but Andrew Kreisberg told us that a minor role wasn’t the overall goal, since “within the body of the series of Supergirl, there is a “Martian Manhunter” series rolling throughout it.” In future episodes, we’ll learn more about the White Martians and Green Martians. We got the meat of the backstory from David:

“The white martian species in our story is responsible for the death of the whole of the green martians. There was a fire, and they burned them. We get to see a lot of that. It’s very emotional.

“The fans are going to be, I think, really delighted to see this, because I don’t think, technically it’s been able to have been done before. But, I think that we’re now thankfully living in an age where we have people like Armen [Kevorkian], our visual effects director who’s just fantastic, and he’s capable of just bringing some of this stuff to life, so I think fans are really going to get to see a version of Martian Manhunter on the screen that’s just never, ever been seen before.”

Part of that backstory will include the character Jemm, a “son of Saturn” from the comics who has some unfinished business with Martians.

Hank’s Relationship with the Danvers Sisters Is About To Change

Supergirl Pilot Preview Trailer Supergirl Interview: Hank Henshaws Secret Identity Revealed


Hank Henshaw and Alex Danvers have been working side-by-side at the DEO from the beginning. While Hank is usually viewed as gruff and stand-offish, Alex and Kara are going to get a different view of Hank following the revelation of his true identity. Andrew Kreisberg described it as a unit:

“[We’re] watching this relationship that’s growing between him and Alex, and him and Kara, that started out at a very gruff place, and then by the time you’re getting into the meat of the season they’ve become this little family unit. He’s become a surrogate father for them, but at the same time they’re helping him become more human.”

Chyler Leigh, who plays Alex, and who will be the closest to Hank/J’onn explained it this way:

“Up until then it’s all the questions of who was Hank, how much does he know about our past and family, and now I’m kind of learning more he’s very much a part of what happened to my dad. It definitely adds a lot of layers to the relationship between them. You start to see that he looks at her almost as if she’s one of his daughters, one of his children. It’s been really cool watching that arc. The revelation, when it does come out, it’s pretty intense.”

Alex’s reaction will balance between heart and head, having to deal with realizing that her former mentor and superior officer is now another alien for her to study:

“She’s a scientist so it’s like she’s asking him questions because he’s the great Martian. He’s like the only one left. She’s just mind-blown because he’s literally the last one. It’s asking a lot of questions. There’s a balance between the scientist in her and also the personal side of it.”

As for Supergirl herself? Melissa Benoist simply stated that “I can’t wait for you guys to see it. It’s a good thing; she’s really happy about it.”

Martian Manhunter’s Coming Out Won’t Be Like Supergirl’s

Supergirl Martian Manhunter Hank Henshaw Supergirl Interview: Hank Henshaws Secret Identity Revealed


J’onn J’onzz has a lot to contend with as he works with Supergirl. While the world may welcome (or criticize) their latest superhero. they may not be quite ready for a little (big) green Martian.  David Harewood explained that even in the world of alien visitors, looks matter:

“That’s something very uncomfortable for him because he realizes Kara’s beautiful, attractive, and blonde, and gorgeous, and I’m this 7-foot green martian. And, as much as I just want to be myself, it would terrify people to be confronted with this alien. So, he still has issues that he has to deal with.”

Having lost his people will give J’onn and Kara something in common, but where that loss gave Kara plenty of rage, Harewood says it worked out differently for his character: “having lost his own children, he’s got a lot of pain and a lot of melancholy, which is fantastic to play.” That duality was repeated by Andrew Kreisberg, claiming that the character’s “soulfulness and sadness” mean he is “the most frightening-looking of all the Justice Leaguers and, yet, is the one with the purest heart.”

What’s His Mission on Earth?

Kara came to Earth in order to protect Baby Kal-El. Villain Astra has her own motivations for plotting against Earth. Martian Manhunter has his own thoughts for sticking around. Andrew Kreisberg described it as a mission:

“If he survived Mars and came here, and his whole goal was to protect Earth and not let Earth suffer the same fate as Mars. Well, then, he’s doing exactly what Kara says and what Astra says, which is, ‘Not here. Never again.’ He’s had to lead this crazy existence, pretending to be Hank Henshaw.”

Not a Moment Too Soon

Supergirl Human For a Day still 2 Supergirl Interview: Hank Henshaws Secret Identity Revealed


Besides villains like Toymaker and Silver Banshee popping up soon, we can’t forget about this season’s Big Bad, Aunt Astra. Soon to join her will be Non, known primarily from the Richard Donner Superman films. But Ali Adler clarified what we’d be seeing when it comes to Non. Ali Adler compared the two by referring to Donner’s version as “a post-lobotomized version and this is a [pre-lobotomized version]. Not that we go into the lobotomy. But it’s a pre-lobotomy. It’s a very brilliant Non. A force to be reckoned with.” She also confirmed that the character’s voice has been heard off camera before.

With these super villains joining forces, Supergirl will need all the help she can get from Martian Manhunter. But what do you think of the character’s design? Are you happy to hear the important sides of the character are priorities, or had you hoped to see a different approach? Share your thoughts in the comments.

Catch Supergirl Mondays @8pm on CBS.