John Cena's Peacemaker is back, and he's not alone. In the upcoming HBO Max series, A.R.G.U.S. Director Amanda Waller will send the ex-Task Force X member and some of her agents on a new, off-the-books mission. Now, Chris Smith will team up with The Suicide Squad alums Emilia Harcourt (Jennifer Holland) and John Economos (Steve Agee), as well as newcomers Clemson Murn (Chukwudi Iwuji), Leota Adebayo (Danielle Brooks) and Vigilante (Freddie Stroma) -- but none of them will be prepared for what they're about to face.

Speaking to CBR, Cena and Holland offered a glimpse at where Peacemaker will take their characters. Cena explained why he loved putting on the uniform, while Holland shared the joy of working with the stunt team to perfect the show's action sequences. They also discussed the inherent danger of vulnerabilities in their characters' line of work, why Peacemaker "gamifies" his approach to heroism and more.

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CBR: What were you most excited to explore with your character in Peacemaker, that perhaps you didn't have the time or space to do in The Suicide Squad?

John Cena: Oh, for me, it was just getting the chance to do something I loved. I really loved putting on the uniform, and being such an interesting character. It's why I wore the uniform on the red carpets and wore it to interviews, and I really had a lot of fun with it. When you have that much fun with something, of course you want to do it again! So the chance to be able to do it again, no matter what it entailed, that was a pleasure for me.

Jennifer Holland: I didn't think that I was going to get the opportunity to play this character again ever, so just everything that I got to delve deeper into was a joy for me. But I think the thing that was the most fun and that I was so excited to explore was the physicality of the character, getting to learn all of the fight choreography and getting to spend all the time with the stunt team and that fight team and learning all of the tactical training that I got and everything like that. It was a chance to meld the physicality of who I am with my acting job, and it was a joy. I had such a great time.

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Both Peacemaker and Harcourt have these hardened exteriors to hide their vulnerabilities. How did you approach the balance to these two disparate sides of your character?

Holland: I think that when I set out to explore who a character is, I just really delve deeply into what makes them who they are, what their childhood was like, and what brought them to the place that they're in. I think that figuring out who Harcourt is and what makes her as hardened is as she is was really interesting for me.

I think the obvious parts of that are that when you're working in a job where you're killing people and seeing people die all the time, I think, generally, in order for you to not fall apart emotionally, you do have to close yourself off. Vulnerabilities become -- it can become dangerous to you in this line of work. So talking about it in a serious perspective, it's practical for her to not allow people to affect her in any way. So yeah, that's what I delved into.

Cena: I think from Peacemaker's perspective, that persona is more boastful. I would see his perspective as the eyes of somebody in a first person shooter game, and that's why he gamifies his marksmanship and his skills. I just think he is like most loud, brash individuals: they are putting up a front to defend from people to understanding who they really are.

Peacemaker's first three episodes debut on HBO Max starting Jan. 13.

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