DC Comics fans were pleasantly shocked last month when it was revealed that David Harewood's "Supergirl" character, Hank Henshaw, was secretly long-running superhero and Justice League regular Martian Manhunter. It was a true red herring, given that Hank Henshaw in the comics is the Cyborg Superman, leading viewers to guess Harewood's character would have taken a very different turn from what the show delivered.

CBR News spoke with veteran director Glen Winter -- who directed next week's "Supergirl," "Strange Visitor From Another Planet," plus the two-part "DC's Legends of Tomorrow" pilot -- about Monday's J'onn J'onzz-centric episode, which he promises to be both emotional and action-packed.

RELATED: "Supergirl" Adds Daniel DiMaggio as Young Kal-El

"It's an amazing episode," Winter told CBR. "It delves into Martian Manhunter's history, and where he came from. Someone from his past comes back to see him. David Harewood gives an emotional, nuanced performance. You can expect to cry. It's beautiful. [Audiences] can expect some amazing action."

Of course, with Harewood's Martian persona being nearly all computer generated, that means there's an added level of difficulty when filming scenes featuring the hero. And that level is raised even higher when said scene involves a lot of action, which is something Winter is known for. "At some point, there was some really complicated sequences with an all-CG character. I'm not used to shooting fully CG characters," the director explained. "Sometimes you get more inspiration from what you are limited by. You have to figure out a way around it. That drives the way you approach a scene. Sometimes I'm used to working in particular confines. For this episode, where you have a creature that is completely digital, you can do anything, so I was a little overwhelmed. I'm used to someone telling me I can't do something, and then I have to figure out how to work around that. It's just funny -- it took me longer to get my head around how to do it, because I could do anything.

"There's also a sequence at the end which is one of the most complicated, almost entirely CG-created sequences that they've done so far on the show."

"Supergirl" airs on Mondays on CBS at 8 PM ET.