Danielle Panabaker breaks down The Flash series finale surprise reunion: 'How I wanted to go out'

Warning: This article contains spoilers for the series finale of The Flash, "A New World: Part Four."

Danielle Panabaker got to end The Flash the way she started: As Caitlin Snow.

In the 2014 series premiere, the actor starred in the CW's Arrow spin-off as the brilliant scientist, but over the course of nine seasons, she added many more roles to her resume. From metahuman villain-turned-ally Killer Frost, to the definitely evil metahuman Hellfrost, plus multiple multiverse dopplegangers, and ultimately the goddess Khione, Panabaker ended up spending more time as alternate characters than as Caitlin in later seasons. Thankfully by the end of the series finale, Panabaker was back in her original role as Khione ascended and Caitlin was returned to her body, reuniting with the rest of Team Flash.

Below, Panabaker tells EW about how Caitlin's return is the happy ending she always wanted. Plus, the actor breaks down what it was like saying goodbye to The Flash as only one of three remaining original season 1 series regulars.

Bettina Strauss/The CW Danielle Nicolet as Cecile Horton , Jon Cor as Mark, Danielle Panabaker as Khione, Kayla Compton as Allegra Garcia, Brandon McKnight as Chester P. Runk and Grant Gustin as Barry Allen on 'The Flash'

ENTERTAINMENT WEEKLY: What was your reaction when you found out Caitlin was returning in the final scenes?

DANIELLE PANABAKER: Great. It was how I wanted to go out. It's how I joined the show, and it was appropriate that that's how I left the show as well. When [showrunner] Eric [Wallace] initially conceived season 9, he thought he was going to have season 9 and 10 to tell a lot of stories. I think it snuck up on him and the writers how quickly they needed to wrap up so many storylines. I did feel pretty strongly, and I was pretty vocal about this, that it would only be right to bring Caitlin back again to honor the show and how we started. That's not to say that she hasn't grown and the other characters I've played have been a lot of fun, but I was invested in that. I do feel that, for me, the show ends on a hopeful note and that is what I will choose to focus on and take away from this show.

What was it like as you were changing from Khione into Caitlin for your very last scene?

It was fun. We've spent hours upon hours upon hours changing me from Killer Frost to Caitlin or Caitlin to Killer Frost. There was even one episode last season where I played Hellfrost, so I would be Caitlin and then Killer Frost and then Hellfrost and go back and forth. I've spent quite a lot of time changing on this show.

You've definitely played more characters than most — the only person who beats you in that regard is Tom Cavanagh.

And it's a little different for him because he did a lot of his characters just as a one-off. They'd pop in for a scene or two and it was fine versus having to maintain the consistency and the arcs of Frost, and then this season, Khione. He could go for the humor a little bit more in a way that I couldn't necessarily.

Throughout all nine seasons, how did you approach keeping all the different characters separate as they each had their own arcs?

That's the work of an actor. You do that even when you're not playing multiple characters. We don't shoot in sequential order, so it's important to know the script and to have done your homework, and even 184 episodes in that was something that I still took seriously, trying to make sure I knew where we were coming from and going to. When we're filming multiple episodes at once, it can get confusing, but that's why it was helpful to have writers on set, and our script supervisors were stellar at helping us keep track of stuff. That's why it's also important to have a strong director as well.

Katie Yu/The CW Jon Cor as Chillblaine and Danielle Panabaker as Khione on 'The Flash'

How were you feeling going into your series wrap?

It was quick. Most of the day had been going by a little bit slowly, and then, as Caitlin, we only did one or two setups and then that was it. It was nice to go out that way. I'm proud of what we did and accomplished.

Your speech thanking the cast and crew for all their hard work was so powerful. Did you have that planned in advance?

I knew I wanted to say something. I try to approach things from a place of gratitude, because we are so fortunate, and that speech really was for them. It's not the first time I've given a speech like that, but it was the last. It's really easy to give actors all the air and the space in the room — and a lot of times, actors require it. But to get to acknowledge the crew, the people who work just as hard, if not harder or in a different capacity than I do, than we the actors do, and they don't get credit or acknowledged for that in the same way that actors do.

What did you do after your speech?

I said my goodbyes. I'd been processing it, but this is not the first show I've ever done. It's certainly the longest show I've ever done, but I know that the people I'm close with, I will continue to have a relationship with and get to talk to and hopefully see again, so it didn't necessarily feel like it needed to be one big goodbye for me.

Were there any tears that night for you?

You want to know what's funny? I didn't cry when we wrapped. The next day, they had some green screen pickups because Grant [Gustin] had COVID during our last episode, so there was some creative filming that had to be done and they were going to have to add him in, so they had a little bit of work still have to do the next day. And I opened the call sheet to look at the next day and at the bottom, our line producer had written a note, and that's what made me cry. I read it, I laughed, and started crying. I don't know, that's what got me.

What was your reaction when you learned that The Flash would end this season?

I had just had a baby, so I wasn't really thinking about the show that much, to be honest. I had a few other things on my mind. [Laughs] Grant FaceTimed me and he said that he had decided he was ready, that this would be his last season of The Flash, and I guess the studio and/or the network had also decided that it would be the last season of The Flash, and they wouldn't try and continue with someone else. And I laughed at him, because that was not the first time that Grant had told me that he was done with the show, that he was moving on, etc. Many times over the last nine years, he's felt that way about this show and gone so far as to make phone calls and tell people that he was ready to be done. I really believed season 8 was going to be his last year. When he told me, "No, season 9, this is really it," I laughed at him and basically said, "Gee, I've heard this song and dance before." And then when it broke in the press, I texted him and I said, "Okay, I believe you this time."

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