‘9-1-1’ Star Oliver Stark Says ‘Ego’ Will Cause Tension Between Buck and Eddie in Season 10

9-1-1 We may only be halfway through the emergency of the three-part Season 10 opener, but an erupting volcano in downtown Los Angeles is already the least of a character’s problems.

Last week’s ABC series premiere saw Oliver Stark’s Buck struggle to understand 4-year-old Theo (Lincoln and Teddy Sykes), his biological son coming to live with him after his parents were killed in a car accident in Season 9. Theo’s unruly behavior only caused growing tension between Buck and his best friend, Eddie (Ryan Guzman), who was clearly frustrated by Buck’s hesitance to discipline his child.

While Eddie – already father to teenager Christopher (Gavin McHugh) – managed to bite his tongue for the majority of the episode, things came to a head at Eddie’s home when a hyperactive Theo crashed straight into Chris, who had cerebral palsy, causing him to fall. Theo immediately apologized, but Buck suggested they leave, leaving Eddie to say, “Yeah, maybe you should.”

For Stark, the moment is complicated and multi-layered. “(Buck} is obviously horrified that this thing happened,” Stark said. Weekly Entertainment. “But this moment is interesting to me because there was no malicious intent, right? This is the four year old being four years old. So while Eddie is certainly right to be angry, and Buck is right to be embarrassed and horrified that this happened, there is only so much mitigation you can do for a four year old, and certainly one who has suffered so much trauma.”

Stark notes that while everyone watching the scene can “agree” that the incident is “horrible” to witness, it’s also not exactly “cut and dry.”

“It’s difficult to point fingers and blame to a large extent because it’s just a difficult situation,” he adds.

That said, Eddie and Buck are clearly on different pages when it comes to their views on how Theo should be raised – and Stark says these opposing opinions will slowly come to a head as season 10 continues to unfold.

“I think you can only bite your tongue for so long, especially when you’re invested in the situation and you care about the outcome,” Stark says of Eddie’s mindset. “So I would say there will be less tongue biting as we move forward.”

And while Stark admits that Eddie should be the “easy answer” when it comes to who Buck turns to for help with Theo, there will be “other things at play” that will change those circumstances – including Buck’s complicated feelings about getting advice from his best friend.

“I think there’s some ego at play for Buck that’s going to get in the way,” Stark teases, noting that his sister, Maddie (Jennifer Love Hewitt), will be someone Buck can more easily lean on. “He’s not going to blow up at Maddie,” Stark explains. “I don’t think his ego will be as affected if Maddie expresses her concerns to him. And we’ll see some of that as we move forward.”

So why can Buck accept criticism from his sister but not from his best friend? “I just think the sibling relationship is different,” Stark says. “And I also think that Buck has been there on a lot of different levels for Eddie, helping Christopher and playing a role there. So to have Eddie question his methods, I think that will be like a blow. Because he’s shown up for Eddie so many times in the past.”

Stark hints that all of this – including learning why Buck is so lenient with the rambunctious Theo – will start to unfold by Episode 3.

“We’ll kind of learn where Buck’s head is,” he continues. “Theo’s been through a lot…I think (Buck) is just acting with the best of intentions and at least to some extent doing what he thinks is right. He’s just trying to figure it out, and he just wants everyone to be happy.”

As for why Buck and Eddie find themselves at odds so often lately — despite clearly liking each other — Stark attributes it to the duo being “very passionate” people who are “set in their ways.”

“They argue because they often both believe they are right!” he said laughing. “And the reality is that none of them are really wrong, especially in what’s coming up (this season). It’s just not black and white where one is right and the other is wrong. There are difficult, confusing, difficult situations that they’re trying to navigate right now, and there’s no right answer.”

Speaking of tough situations to deal with, Stark is facing his own challenge behind the scenes this season after injuring his leg during filming. Although the actor claims that no storyline for Buck needs to be changed – “We’re still in an emergency and we’re still getting there!” he told EW – the 9-1-1 The team has become “creative” in the way they film things.

Thanks to a great team, Stark says it’s been “fun” figuring out how to keep going “day in and day out,” warning the audience that they might see a lot of Buck’s shots “from the waist up” for now.

“I am very grateful for the accommodations the crew made for me,” he continues. “And we have guest directors coming on the show, and some things we have to make sacrifices for. So I know we want to get that shot, but it’s going to be difficult to do it, so everyone has been really, really accommodating and really embraced the challenge of dealing with it.”

A broken leg certainly hasn’t reduced Buck’s screen time this season. The actor even makes an appearance on a sister show 9-1-1: that of Nashville second episode, when Ryan Hart (Michael Provost) calls to ask for advice on how to get a baby out of a pipe – an emergency the 118 faced in their pilot episode eight years ago.

Weighing in on such a familiar crisis, Stark reflects on his own journey with Buck over the years.

“If we go back to Episode 1, Buck was very green back then and too hasty. Now he’s the one giving the advice,” Stark says, teasing that Buck’s past will be referenced in Episode 1. Nashville. “But it’s different now, and it’s definitely a nice nod to the journey Buck’s been through.”

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As for continuing to develop Buck’s relationship with the Nashville going forward, Stark is completely on board with the idea. When asked what he thought about the fact that some fans wanted to see Buck spark a romance with Provost’s Ryan, Stark initially doubts it was a request — “I think you made that up,” he jokes to EW — but ultimately confirms he’d be up for the challenge. “Michael is great,” he said with a smile. “I’m always open to anything.”

9-1-1 airs Thursdays at 8 p.m. ET/PT on ABC. Episodes are available for next-day streaming on Hulu.