9-1-1: Nashville Star Chris O'Donnell on Don's Unexpected Family Reunion: This 'Has Been Weighing on His Mind Forever'

[Warning: The following contains spoilers for the series premiere of 9-1-1: Nashville, "Pilot." Read at your own risk!]

Don Hart's (Chris O'Donnell) life will never be the same. In the series premiere of 9-1-1: Nashville, which combines the high-stakes rescues of the beloved first-responder franchise with the distinctive flavor of Music City, the fire captain of Station 113 finally comes face to face with Blue Bennings (Hunter McVey), the son he fathered years ago during an ill-fated relationship with his ex, backup singer Dixie (LeAnn Rimes).

Don has thought about this first meeting with Blue for years, but what he likely didn't anticipate was having to introduce his other son, Ryan (Michael Provost), who also works as a firefighter at the 113, to his half-brother at the same time. Desperate to make a quick buck, Blue has agreed to dance at a strip club in a firefighter outfit. While being scolded outside by one of the managers for breaking one of the rules of stripping (go figure?), Blue witnesses the crash of a pedal bar that was hosting a bachelorette party. He then springs into action and catches the attention of the first responders who answered the 911 call — two of whom happen to be Don and Ryan, who was completely unaware that he had another sibling living in the same city where he grew up. (Talk about an awkward family reunion.)

"Don knew this was getting close because Blue had been reaching out to him, and Ryan knows something's wrong. He just knows it. He's like, 'What is going on, dude? Why aren't you telling me what's happening?'" O'Donnell explained to TV Guide. "He's about to tell him and another emergency [call] comes in, and lo and behold, they all come face to face. So Don knows what a sh--storm this is going to cause with his family and the station and everybody. But at the same time, this had to happen at some point."

Don may be relieved to finally get to know Blue, who takes his biological father up on his offer to be the 113's new "probie" — or rookie firefighter — by the end of the premiere. But needless to say, the two women in Don's life will find themselves at odds with each other. As Dixie secretly encourages Blue to "sink [his] hooks" into the Hart family and their deep pockets (in part to help fund her own surgery to remove polyps on her vocal cords), Don's wife, blue-blooded businesswoman Blythe (Jessica Capshaw), begins to suspect that the Benningses have ulterior motives for showing back up in Don's life.

Below, O'Donnell breaks down how Don straddles two different worlds as a working-class firefighter who married into an aristocratic family, how this familial twist will set the wheels in motion for the rest of the first season — and how his short time in the fire captain's chair has already changed the way he thinks about first responders.

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Unlike Bobby Nash (Peter Krause) on the original 9-1-1 and Owen (Rob Lowe) on 9-1-1: Lone Star, who were both transplants and found fresh starts by rebuilding a fire station outside of their hometown, Don seems to be born and raised in Nashville — or at least he has spent a significant amount of time creating a life for himself in the city. How have you thought about building him as a character? What do you think makes him tick?
Chris O'Donnell: Well, was he born and raised in Nashville? That's all stuff that was still coming together as we were filming. They're like, "We're going to start filming on this date." I go, "We're still kind of working out who this guy is," but there's a schedule and they got to get on it. So for me, it was really just making the emotional connections of what these characters are going through, and obviously Don specifically, and taking it from that level. And then you start to add in a little bit of where he's from.

His wife is a blue blood, and he's from the other side of the tracks and didn't grow up with a family. His family at the firehouse is as much a family to him as his wife and his son, and obviously there's a lot of history that the audience learns about in the first episode here. He tries to be the best man he can, but he's haunted by some of his past. He knows he's made some mistakes, and he's always trying to make up for that. He's just trying to lead by example [when he's] on the emergencies on site when he's with his crew, but also just in life with his son and those around him, just being the adult in the room with them and trying to set a good example.

How does Don straddle these two very different worlds that he is a part of? Is he completely comfortable in the upper-class environment, having grown up in more of a working-class family?
O'Donnell: I think he's comfortable, except when his father-in-law is around. I think there's definitely a lot of tension there, and I think, as far as he's concerned, the root of a lot of his problems over the last 25 years has been the father-in-law's inability to accept him into the family. [His father-in-law thinks] that he's just never good enough because of where he comes from and what he does for a living. And I'm sure it just gnaws at the father-in-law that his grandson, who could have done anything and probably went to all the best schools growing up, chose to follow in his dad's footsteps and be a fireman. It's just driving him crazy. So there's drama going on here.

The pilot quickly reveals that Don has two sons — there's Ryan, who followed in his firefighting footsteps, and there's also Blue, who recently reached out to Don after finding out his paternity from a 23andMe-type test. When he's at the rodeo with Ryan at the start of the pilot, Don may be physically present, but his mind clearly appears to be elsewhere.
O'Donnell: This is something that has been weighing on his mind forever. First of all, he's got enormous regret that he wasn't able to be a part of this kid's life. The fact that he hasn't been able to tell his son about it is killing him, and he knew that at some point in his life he's going to have to face this day. I think a lot of people go through things like that where they're living with a secret, or they've got something, and it's just gnawing at 'em. And frankly, at a certain point, as much shock and anger and drama kicks up, I think, for Don, there's a certain sense of relief, like, "Oh my God, I got that weight off my shoulder." You know what I mean?

Living in a lie is tough for people, and sometimes just let the chips fall where they may and you might be better off. So this thing came to a head. [Blue] had been reaching out to [Don], and he honestly didn't know how to respond. He knew this was going to really cause problems, and then all of a sudden under these crazy circumstances, they run into each other — and it all comes out. So I think on the one hand, he knows he's got an uphill battle trying to explain this to Ryan. But on the other hand, he's suddenly got a chance with his other son, Blue. He has always wanted to be a part of his life. 

Don and Blythe have known of Blue's existence for years, and they've been trying to support him from afar for years, but it's certainly one thing to think about Blue in the abstract and another thing to now see him in the flesh. How will the everyday presence of Blue affect and test Don and Blythe's marriage going forward?
O'Donnell: It becomes real. It's like when something happened in the past, you forgive, you forget, you make amends. You move on with life and you're living your life. But every once in a while, things might crop up, and there's a reminder, like, "That thing's still kind of out there." But all of a sudden, you're confronted with something face to face, and this elephant that's been in the room forever is literally in the room now, and you got to face it and see if your relationship holds up as strong as you believe it to be. That's a lot to deal with.

How would you characterize Don's relationship with Dixie? What we do know from the pilot is that they were from the same side of the tracks, but Don married into wealth.
O'Donnell: They have a lot of history, and that will be revealed about halfway through the season. But she knows him as well as anyone and has an appreciation for what he's gone through in his life, and there was a real bond there. They were a big part of each other's lives when they were younger, but then circumstances kept them apart and he met somebody else, and there's a lot to be revealed. We're filming Episode 10, 11 right now. So much information comes out in this one episode. It really explains Blythe, Dixie, and Don and how they all came together and how it happened — and you learn a lot.

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You're still relatively early on in the process of playing Don, and the 9-1-1 franchise definitely pushes the believability of this line of work to the nth degree. At a certain point, viewers are left to wonder just how many more natural and manmade disasters can happen in this universe. Even though you're playing in such a heightened world, how has making this show already changed the way you think about first responders?
O'Donnell: It's funny. I was just taking a car into [New York City for a press day] and going over the bridge and there was an accident, and all the firemen are out there and they have different color jackets than us, but I looked at it completely differently — just looking at how they're handling the equipment, who's in charge. I was passing quickly, but there had to be 10 firefighters on the side of the road, and I was like, "Wait a second, are they shooting something? No, no. Those are real firemen. This is really happening."

But there are moments where I've been on the set going, "You can't be serious. There's no way this could happen." They're like, "No, it did happen. Look it up. Google it." I'm like, "Really?" And that's not always the case, but I'll be damned — so many of these instances where I think, "You guys cannot be serious with this storyline," and they did happen. I think part of it is just the fun of the show. And sometimes, there'll be multiple emergencies in the show, and one of them will be just this crazy thing that's an offshoot, a one-off type thing, and then there's kind of the big one that drives the story. But that is the world; that is the show. It is, as Rashad says, about these kinds of spectacle emergencies. That is the brand.

9-1-1: Nashville airs Thursdays at 9/8c on ABC. Episodes stream the next day on Hulu.