Central City's Detective Joe West has encountered some pretty menacing super-powered adversaries since S.T.A.R. Labs' particle accelerator exploded. So far, they've all been human in nature, but that's a streak that's about to end because tonight, the savage primate Gorilla Grodd is unleashed.

Introduced by DC Comics' "Flash" team of John Broome and Carmine Infantino in 1959, Grodd was once an average ape until an alien crash landed on Earth and imbued him with super-intelligence and psionic abilities. The CW series reimagines Grodd as a lab experiment gone horribly wrong -- or right, depending on your point of view. Tonight, after lurking in the shadows over the last few months, Grodd finally makes his move, targeting the Flash and Joe.

RELATED: Grodd Speaks in New Clip from "The Flash"

Ahead of tonight's episode, Jesse L. Martin spoke with CBR News about Joe's confrontation with Grodd, the newly revealed villain's head games, how Joe will continue to protect his daughter Iris now that she has learned the truth about Barry, and what to expect from the wrath of Harrison Wells. Plus, Martin hints at Barry's potentially game-changing decision to come in "The Flash's" Season 1 finale.

CBR News: There's been a lot of build-up to Grodd's full debut. What makes him such a big threat to the Flash?

Jesse L. Martin: First of all, [his] size alone. He's a giant, so he's just a physical threat to anyone who comes near him, including Barry as the Flash. But, apparently Grodd has been evolving, so he's gaining in intelligence and things like telepathy. That makes any creature dangerous. We learn Joe doesn't even like regular gorilla,s and here he's hunting for a supernatural one.

Grodd has been prowling the sewer system for a while now. What finally brings him into conflict with Flash and Joe?

The fact that Harrison Wells has been found out and has gone missing, if you will. That seems to have some sort of effect on Grodd. It's why Grodd seems to show up out of nowhere. Harrison is sort of the paternal figure to Grodd, or at least that's what we perceive.

Unfortunately, as we've seen in the clips and commercials, Joe gets captured. How dire do things get?

Pretty damn dire. Joe had no idea what he was coming up against. He had never even seen a gorilla in person. Then, when Grodd finally shows himself, I don't have a chance to get away. He keeps Joe in his lair for quite a while.

Does Grodd get in Joe's head like he did with General Wade Eiling?

Yes, he does. Joe can't even believe this thing is real. The fact that it's communicating with him the way it is -- that's the first time that's ever happened to Joe in any way, shape or form, especially dealing with all these different meta-humans. He just can't believe the situation he's in. On top of that, it's absolutely terrifying.

The episode's teaser trailer shows Grodd right up in Joe's face. How was it filming that scene? Were you acting against thin air, or did they have someone opposite you and then digitally removed them?

In the close-up you saw, it was me acting to the air or an "x" hanging on a stick. You can imagine how terrifying it is. It was fun to actually work that way, because you can just assume the worst as far as what this thing looks like and how scary it might be and how close it might be to you.

It's that "Aliens" moment.

No kidding! A lot of people say that -- that's exactly what it felt like.

In the episode "The Trap," Barry had a very bad idea on how to trick a confession out of Wells. What are the ramifications of that plan crashing and burning?

The hard part about that is Wells is always a little bit more prepared and a step ahead of us every single time. That's when we realize it's totally true, and the gig is up because he figures out what we are doing while we are doing it. That has ramifications, because now he knows we're on the hunt for him. That's when things get really bad between us and Harrison Wells and the Reverse Flash.

Joe also didn't give his blessing to Eddie proposing to Iris. In what way does that affect their relationship?

It definitely affects Joe and Eddie's relationship because [Eddie] thought they were getting closer and working well as partners, and that I accepted the fact that he and my daughter were having a relationship. I had accepted that fact, but the idea of it becoming permanent, and me knowing what I know about the future between Barry and Iris -- there's no way I could let him do that. It's going to end in ruin for both of them. I can't have that on my shoulders.

Iris also figured out Barry is the Flash. How does Joe feel about that development?

Joe feels terrible that he kept that from Iris, but he was very sure he was keeping her safe by keeping her in the dark about this information. The fact she finds out, particularly with Iris being the kind of hothead she can be, is a bad thing. She feels we don't trust her with that information, and that's a bad thing with Iris, because she won't let it go right away.

He must freak out knowing the Reverse Flash went after her.

Oh, my God -- yeah. We've learned Barry can't even stop the Reverse Flash at this point, and the guy just keeps showing up. The more I get involved in the investigation and the hunt, the more danger I put Iris in, and Barry -- and myself!

Joe is mostly worried about Iris. Barry is obviously a superhero, so he can handle things she can't. I'm a cop and happen to have a gun, so I might be able to do something. Iris is a young woman who works at the newspaper. She has a pen. It's wrong for me to put all of us in danger, but we have no choice. This guy is literally hunting all of us, so we have to do the same.

After tonight's episode, there are only two episodes left this season. What's on the horizon as we head into the finale?

Particularly in the finale, viewers can expect to see Barry grapple with the notion of really going back in time again to try and save his mom and stop his dad from going to jail. The big story in our finale is, what are the ramifications if he does so? If you go back in time and change one little thing, everything from then on becomes a completely different story.

Barry realizes if he does do this and goes to save his mom, that he won't have the life that we've all seen up until now. It weighs heavily on him, and he asks Joe what he should do. Joe says that if he has the chance to help his mom and dad, then he should do so. The gist of the episode is whether he does or not, and what kind of changes that would make.