The following contains spoilers for the Season 2 finale of The Hardy Boys, "An Unexpected Return."

Something sinister was underfoot in Bridgeport, and it was up to the Hardy Boys to uncover the truth. Inspired by author Edward Stratemeyer's beloved series of novels, The Hardy Boys TV series finds the Hardy family-- 16-year-old Frank, 12-year-old Joe, and their father, Fenton – arriving in the small town following the tragic death of their mother/wife, Laura.

The Hardy siblings soon stumbled upon a case involving their grandmother Gloria, the magical artifact known as the Eye, and the Circle of the Eye, a cultish allegiance dedicated to harnessing its supernatural properties. The Season 1 finale culminated with the Hardy Boys destroying the Eye, but not without consequences. Season 2 quickly established that Frank had become imbued with the Eye's supernatural power and that he may not be in control. Rohan Campbell, who portrays Frank, recently spoke with CBR about sleuthing, superhuman abilities, that game-changing finale, and Season 3.

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Frank Hardy Season 2 Woods

CBR: There was a four-month gap between Seasons 1 and 2. How do you feel Frank changed and grew during that period?

Rohan Campbell: During the four-month gap for Frank, he's just trying to settle in and get to know himself in this new town, be a real teenager and enjoy himself for the first time now that all this chaos has settled. He has completely let go of it. It's the only way to cope. His little brother, Joe, is obviously not a fan of relaxing or letting Frank relax. What's interesting is during the four-month gap, you get to watch Frank sort of become a real teenager again.

What I love about the start of Season 2 is how fast it all gets ripped out from underneath him. I think it's really fun to see Frank as a person having fun, goofing around, and playing with his brother without the stakes involved in that first couple of episodes. It's fun to see how exasperated Frank is with Joe. It's a great brother dynamic, which to me is what Frank really is: a brother.

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Frank became a vessel for the Eye. In what ways did that add another layer not only to the character but to the storytelling this season?

How do you empathize or relate to having a magical space rock inside your body? What it did for this season is it added this element of Frank having absolutely no control. It added this element of, "How much can you trust it?" Frank played this game of trust with the Eye. When you watch the first season, near the end of it, the Eye starts to mess with him a bit. What it does is it gives Frank answers, but we get to see him choose to be an actual detective, which brings us right back to the source material and what those brothers actually are.

When I read the scripts and fell in love with the idea, I was like, "This is genius. Now you get to see Frank make a choice to be a practical detective and fight against something he has no control over." It moves the story forward fast this season. I think it's over four days.

Who is a better detective? Frank or Joe?

Look, you can't have one without the other. That's how I look at it. If Frank was in charge of something, he would never throw himself in danger enough to get it off the ground. I think Joe needs to be protected. That's me just empathizing with Frank in this show. I don't know, man.

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Hardy Boys Callie Frank

How much fun was it to, as Joe says, play superhero in the Hardy Boys setting?

That's incredible. It's also the world that we built, as well, this '80s world. As big as it is, it is brought down to realism. It has been so much fun doing the superhero thing. The VFX stuff at the end of Season 1 was so exciting. I remember seeing that and being like, "That has to come into play in this season because Frank has his vision superpower, which is betraying him at times."

It was exciting for me just to be a viewer in the sense that I don't know the story ahead of time. I get to read these scripts in real time. It was exciting to see it unfold. It does feel like a superhero thing. Who doesn't want to see into the future? Who doesn't want to predict everything? The strange reality that comes with that is if it is actually helpful when you only have half the answer.

One of the more lighthearted sequences revolved around Joe guessing what abilities Frank must have now.

That scene is amazing. We talked about that a lot on set. We would be like, "What superpowers would everybody have if we could have them?" There was a lot of invisibility. Somebody said, "Perfect charisma would be an amazing superpower."

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What made the Bridgeport Demon and the disappearance of student Dennis such a compelling case to delve into this season?

What I loved about the opening of the season is it starts out like the Hardy Boys books. You think you have a handle on the scope of the story, which is how I feel every time I open a Hardy Boys book. I feel I have a handle on what's going to happen. In this season, there's something as simple as a kid missing. A kid goes missing in the woods. It's something that everyone in town thinks they understand. What I loved about it is it's just so unassuming. It's a simple way to start the story and take us on an adventure that obviously leads down a rabbit hole of chaos that we set up in Season 1.

At the beginning of Season 2, Frank just wants to be a normal teenager. How proficient is he at juggling normal life with these mysteries and being put in harm's way?

It's almost like he's not dealing. What's great about this season is you get to see him try and deal with it, even down to the Callie Shaw relationship, where he's trying to hold down a relationship in the middle of having superpowers. That's what makes any great story, any great comic, any great book, is watching a character try their best to deal with those situations. For me, it feels a little firsthand because you get to live through it all. The unwavering support from the friend group in this second season is so much fun.

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Hardy Boys Frank Joe Talking

Let's talk about the finale's cliffhanger. Frank's great-grandfather has now possessed Frank's body. What was your reaction when you read that in the script, and what does it mean for Frank going forward?

I had read Episode 9, and everybody else had gotten 10. I was working really hard on trying to stay focused on 9 because we work a lot of days. You just try and stay focused on the episode you are in. Everybody else had read Episode 10, and they were coming up to me and were like, "This is insane." I was like, "I know what it is. It's going to be the teacher, and it's going to be this consciousness in a crystal thing." Then, when I read it was the grandfather from 100 years back puppeteering this massive plan, my jaw hit the floor. I remember going, "I knew nothing. I was not even close to guessing that ending." What an amazing twist for the end of the season. To have Frank's great-grandfather be this mastermind was such a smart way to deal with it and realize there's still a lot more in play with Gloria and her betrayal.

What it means for Frank going forward is, hopefully, fingers crossed we get another season [to deal with] how Frank is going to get the hell out of there. Again, I think he's going to have to rely a lot on that friendship group that he has. It's going to be interesting to see Frank figure his way out of a room, so to speak. That will be the next greatest mind test, I suppose.

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Even though Frank's great-grandfather is inhabiting his body, that doesn't necessarily mean he knows how to replicate the way Frank walks or talks or his mannerisms. If you had to guess, which one of Frank's inner circle would figure out something isn't quite kosher with him? Joe? Callie? Fenton?

I love the idea that it's Callie. The way that the season ended with that breakup in the attic and him being so cold to her, I think she is going to piece together what happened in the crystal room. I would love a Callie Shaw episode with her figuring out what happened on her own and then having to convince Joe of this thing, and Joe being, "Yeah, it's weird. He's not acting like himself."

Also, the next great adventure for me, as an actor on this show, is figuring out how to move like a 90-something-year-old grandfather and how to halfway hide that. I think maybe Frank's dad would notice. What's going to be interesting is to see if his dad realizes there is more at play, as well.

Catch Season 2 of The Hardy Boys streaming now on Hulu and airing Monday nights in Canada on YTV and live and On Demand on STACKTV.