Star Trek: Strange New Worlds' Cillian O'Sullivan Addresses Chemistry With Spock & Chapel, Hints At Korby's Dark Side

Cillian O'Sullivan joined Star Trek: Strange New Worlds season 3, and the Irish actor has made an immediate impact as Dr. Roger Korby. Known as the ex-fiance of Nurse Christine Chapel in Star Trek: The Original Series, Korby's romance with Chapel (Jess Bush) is now being explored fully in Strange New Worlds.

Dr. Roger Korby debuted in Star Trek: Strange New Worlds season 3, episode 2, "Wedding Bell Blues," where he drew the ire of the omnipotent cosmic trickster, Trelane (Rhys Darby). O'Sullivan returns as Korby in Star Trek: Strange New Worlds season 3, episode 5, "Through the Lens of Time," an episode which hints at what's to come for the character.

ScreenRant interviewed Cillian O'Sullivan about stepping into the role of Dr. Roger Korby, his lifelong Star Trek fandom, his chemistry with Jess Bush and Ethan Peck, and the possibility of Cillian reprising his role as Devlin in Daredevil: Born Again season 2.

Cillian O'Sullivan Grew Up A Star Trek Fan

He Also Reveals His Star Trek Dream Role

Before booking the role of Dr. Roger Korby, Cillian O'Sullivan was a "massive" Star Trek fan growing up. "I'm a huge Trekkie," O'Sullivan declared. "I've seen Star Trek: The Next Generation, Voyager, Deep Space Nine, The Original Series multiple times over. I've probably seen The Next Generation, like, all episodes, every season, about seven times throughout my life. My father is a massive Trekkie. He got me into it. So, yeah, it's just always been a massive thing in my household."

As such, Cillian was "very familiar" with Korby. "Growing up and becoming an actor, thinking, was there any role if [I was in Star Trek]... Who would I play? I didn't necessarily think it would be Korby, but it's awesome that it is." When asked who his Star Trek dream role would be, O'Sullivan goes back to his TNG fandom: "Maybe, and maybe this would be a tragedy if they did, but if they ever remade Star Trek: The Next Generation, I think I grow a pretty epic beard. That's all I'm saying. And I do a crackin' American accent."

Jess Bush Gave Cillian O'Sullivan "Everything" During Their Chemistry Read

Jess' Generosity & Talent Helped Cillian Book His Role As Dr. Roger Korby

Cillian O'Sullivan praises Jess Bush for helping him land the role of Dr. Roger Korby. O'Sullivan explained how their chemistry read happened over Zoom, and praised Bush's generosity and talent: "Jess Bush is such an amazing actor. I think she'd have chemistry with a stone if she wanted to. We did the chemistry read for the auditions, and Jess, in the chemistry read, really gave. She was very generous in that audition."

Cillian explained, "I've been in chemistry reads before, where, you know… And on Zoom, it was on Zoom, too. So, that's a difficult thing to accomplish on Zoom is a chemistry read. Like, it's one thing for an audition, but she just gave me everything that she could in that room. And that was a huge part of getting the role, was the chemistry that we had to get her in that Zoom room. And that was as much of a part of Jess’ effort as it was mine."

O'Sullivan also praised Star Trek: Strange New Worlds' writers for making Korby likable from the jump: "They wrote us very well. And they made Korby likable. It would have been very different if you brought Korby in as the unlikable new love interest, and everybody would just been like, 'Please, just put [Chapel] back with Spock. But we know in canon that Korby and Chapel end up together, and that's where things are going to go."

Why Trelane Hated Dr. Roger Korby According To Cillian O'Sullivan

Trelane Is "An Omnipotent Child"

The events of Star Trek: Strange New Worlds season 3, episode 2, "Wedding Bell Blues," transpired because Trelane took an instant dislike to Dr. Roger Korby and warped reality to ruin Roger's relationship with Chapel. O'Sullivan sums up why Trelane hated Korby: "There's just a couple of qualities about [Korby] that annoy him. And funnily enough, it's a very human annoyance that Trelane takes on. It's a funny little similarity between Trelane's species. We've been insinuated now as to what that is, but it's a human quality that we share."

O'Sullivan adds, "Korby only discovers really what happened right there at the end. And then Spock agrees with Trelane. And Korby was like, 'Well, how dare you.' It was as much of a surprise to Korby as it was to me to figure out that that's why Trelane was doing everything that he was doing. But I guess if you're an omnipotent child and someone annoys you, that tends to be what you're going to end up doing."

Can Spock & Dr. Roger Korby Be Friends?

Cillian O'Sullivan & Ethan Peck Are Friends In Real Life

Taking over from Ethan Peck's Lt. Spock as Nurse Chapel's love interest was a daunting task that Cillian O'Sullivan managed wonderfully. Spock and Dr. Roger Korby are romantic rivals at first, but they also became friends, although, as Spock amusingly says, "Friends is a relative term."

However, Cillian O'Sullvan thinks that Spock and Korby "are friends, but it's just in a very Spock-slash-Korby way. One of the things that they wrote with Korby is his concern for Spock in the beginning. Like, Spock is my love's ex, her most immediate X. A threatening ex! He's an extremely good-looking, tall Vulcan, right? And yet, Korby is trying to play things from concern, from empathy."

"Like, this guy was just in his version of love with this woman, and I'm the new guy, and he plays that carefully. I don't think Korby has any kind of resentment towards Spock. I think the only time a bit of competition comes up is when they're talking about their intellects. And even that seemed a bit kind of playful. I'm actually often very self-critical, but I think that Korby and Spock do have great chemistry, to the point where I was like, 'Jesus, you nearly should have had a chemistry read with me and Ethan as well.'"

O'Sullivan talked further about his great working relationship and chemistry with Ethan Peck: "Me and Ethan, as people, hit it off straight away," Cillain said. "The first scene that I shot was a scene with Ethan walking down the hallway of the Enterprise, and I was kind of just open about how excited and nervous I was, because I'm a huge Trekkie. And we just kind of had this banter back and forth about it. And he was being supportive. I was like, 'Dude, you don't understand how crazy this is for me.' And I was like, 'You know, you're Spock, right?' And he's like, 'Yeah.'"

"And it was just from the get-go, me and Ethan, as people, kind of hit it off. And then, thankfully, the characters had chemistry. But again, the writing, the writing. It was all there in the writing for that episode."

Cillian O'Sullivan Talks About Filming The "Scary" Event Horizon-Inspired Star Trek: Strange New Worlds Season 3, Episode 5

There Are Hints Of Darkness In Dr. Roger Korby

As a fan, Cillian O'Sullivan enjoyed how "Star Trek" his two episodes so far have been. "302 is one of the things that I'm so grateful for, is that I get to be a part of Star Trek as a fan. But the episodes are so Star Trek," O'Sullivan notes. "They really are a throwback, structurally, to The Next Generation, Voyager, Deep Space Nine. They're just such Star Trek episodes. 305 as well. It's pretty scary. It's got that mystery, the dark kind of mystery, and you also start to see the dark side of Korby, a little bit, too, in that episode. It starts to rear its head. So it was a lot of fun."

O'Sullivan also discussed working with Strange New Worlds' AR wall: "The wedding scene in 302 had the AR wall where we were in that dome. But in 305, the atmosphere that it gave to the scenes when we went through the portal, it was very different. It was very palpable. The whole thing just felt very Event Horizon the whole time. I remember from the second that I walked into the AR wall, just looking around at the coloring and the lighting, I was like, 'This feels like I'm in the universe of Event Horizon.' The episode also has some similarities. I think it was inspired by it in some way. But the AR wall contributed so much to everything, just the atmosphere. It was seeing its full effect that it could have on you in a scene."

Cillian O'Sullivan Talks Returning As Devlin In Daredevil: Born Again Season 2

He's A Fan Of ScreenRant

Before his debut on Star Trek: Strange New Worlds, Cillian O'Sullivan impressed audiences with his guest-starring role as Devlin in Daredevil: Born Again season 1, episode 5, "With Interest." When asked about whether he would reprise his bank robber in Daredevil: Born Again season 2, Cillian hints, "So, there were some talks about Devlin doing some more bits. We'll see what happens."

We're also proud that Cillian O'Sullivan is a fan of ScreenRant after our article spotlighted his work as Devlin in Daredevil: Born Again: "Massive shout out to ScreenRant, because you guys gave me a great shout out when you reviewed Daredevil, and you didn't have to do that. You singled me out. And you were like, you know, special shout-out to Cillian. And I was only in like, a few episodes, so I was very appreciative for that. And I went and followed Screen Rant. And I was like, I'm supporting these guys forever."