'Grey's Anatomy': E.R. Fightmaster on the Love Song They Wrote and Kai & Amelia's Romance (Exclusive)

Grey's Anatomy
Liliane Lathan/ABC

The actor talks to ET about writing an original song featured in Thursday's episode.

Spoiler alert! Do not proceed if you have not watched Thursday's episode of Grey's Anatomy. Mild spoilers ahead.

Grey's Anatomy brought Kai and Amelia even closer than they've ever been on Thursday's episode, which saw the blossoming romance between the two doctors reach a new level of intimacy. In the hour, titled "The Makings of You," Amelia stayed in Minnesota for the night and discovered a different side to Kai -- a musical one -- outside the hospital walls.

In real life, Kai's portrayer, E.R. Fightmaster, and their love of both acting and music converged naturally when the opportunity arose for them to write a new original song for Grey's. Featured in Thursday's episode, "Trouble," written and performed by Fightmaster and their Twin bandmate, Mike Aviles, was written with Kai and Amelia's budding romance in mind. (The song will be officially released on Spotify, Apple Music and Amazon Music on Thursday at 9 p.m. PDT/Friday at 12 a.m. EDT.) 

As Kai and Amelia's relationship goes to the next level, Fightmaster expressed deep gratitude to the passionate response from Grey's viewers. "I've been so excited about the fan response," they told ET over the phone on Thursday. "It seems like people were really ready for a very queer plot line and I have had a lot of fun doing it, so it feels great to be doing something that it is making me happy, would make me happy as a viewer and have all these viewers reach out and be so genuinely thrilled."

The actor said it's "been fun" exploring the relationship between Kai and Amelia over the course of the season. "And I think the writers did a good job doing a slow build in the first half of the season," they credited. "And now I think we're going to really start seeing that pay off." Following the episode, Fightmaster discussed Kai and Amelia's future, the challenges they may face and writing an original song for Grey's.

ET: Kai and Amelia are an unexpected pairing. What has surprised you as you go through this relationship over a period of time?

E.R. Fightmaster: It's been really satisfying to explore this romance in this way. You can see the progression, you know what I mean? So when I have watched this season, and I am watching these characters fall in love, I, as an actor, it's been very satisfying to pace out those emotions too. To check in and remind myself of what these things feel like when you are building a relationship with someone, when you are meeting someone for the first time and that electricity is there when the moment in the relationship where you start to really reveal who you are to somebody else. All of those emotions have been exceptionally fun to play.

This episode also gave you the opportunity to showcase your real-life musical abilities when Kai takes the stage and performs a song for Amelia. How did that part of it come about for you?

I got approached by the writers' room in Grey's, who were fans of my band, Twin. They asked me if I would be interested in writing a song for this episode, and so I worked with my drummer, Mike Aviles, and my producer. In about a week's time, we had this song written and recorded, and then I got to get Mike onstage as the drummer in the show. It was a very meta experience. And Mike and I also started in Chicago doing comedy together, so there was some full-circle stuff of being onstage together again in a different way, in an acting way, and as musicians together. The whole time that it was happening, we just kept looking at each other truly shocked and very thrilled.

Liliane Lathan/ABC

When you sat down to write the song you perform in the episode, did you receive any parameters or themes the writers wanted you to touch on? 

I understand this love story very well, you know? So writing a love song with Kai and Amelia in mind, it's not a difficult task. And the excitement, I think, of them doing this kind of long-distance push and pull... that's a very fun place to write from. So the song itself is playfully antagonizing, which I think is a big part of their chemistry, and it was fun to watch. It was an interesting challenge that ended up not really being a challenge at all.

Why do you think Kai and Amelia work?

I think there's a lot of mutual respect there. They are both people who enjoy each other's brains. That's just the baseline understanding of each other is two people whose brains they respect. And then you add on physical attraction and you add on actual chemistry. I do think if you look at Amelia as a character, she has had kind of a run as a little bit of a renegade in the series. When you bring Kai in, Kai's just naturally a rule-breaker just based on gender identity alone, so they are really well-matched in that way. They're grounded in the job that they love and they are exciting in their natural energies. Combining them, I think there was a very effortless chemistry. Also, it's easy and fun working with Caterina and we enjoy each other, so that has been an energy that has also been very easy to bring to screen.

Kai's in Minnesota and Amelia has a life in Seattle. At the end of the episode, Amelia leaves because she has her baby to go back to. What can you tell us in terms of the future of this couple? At a certain point, the push and pull, long-distance thing isn't going to be enough, I'd imagine?

Like all relationships, there are going to be ups and downs. Especially with long-distance relationships, there are going to be complications, so I anticipate that. I do think these characters will have the ability to make something work if that is the direction the show goes, but it's Grey's and your guess is as good as mine.

With the show renewed for season 19, have you had any inkling or conversations about possibly having a presence on the show? 

That conversation has not been had yet, so we're both waiting by the phone on this one.

What do you want people to look forward to in this second half of the season? 

I want the fans of this relationship and these two characters, specifically the queer fans who are seeing themselves and their love onscreen, to enjoy what they're watching. I want them to be patient and I want them to be along for the ride.

Grey's Anatomy airs Thursdays at 9 p.m. ET/PT on ABC.

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