Caitlin Snow has become one of The Flash's biggest mysteries of Season 4. Over the course of Season 3, she involuntarily transformed into the deadly Killer Frost thanks to her metahuman powers, but that may not be the last we see of Caitlin. In the finale, she reemerged at HR's funeral with her signature white hair... and Caitlin's soft brown eyes. At Comic-Con International in San Diego, Danielle Panabaker -- who plays Caitlin and her alter ego -- teased where we will find her character when the show picks back up and reflected on her wicked transformation.
"Here's what I can tell you about Season 4: Those who love Caitlin Snow won't be disappointed. Those who love Killer Frost won't be disappointed," she teased, then added, "It's about a six month jump from the end of Season 3 to the beginning of Season 4, and I'm not at STAR Labs."
She also confirmed that Caitlin Snow is a part of Killer Frost, if only through Caitlin's memories. "I think you did see moments at the end of Season 3 where Killer Frost, even when she is sort of out, she does have some of the same memories as Caitlin Snow," she said.
Though she kept mum on just about all things Season 4, Panabaker did open up about her role in Season 3. For instance, she shared that she had no idea that Caitlin would become Killer Frost so early on in the show's run. "You know, I've looked to their other shows and Arrow in particular, and Katie Cassidy's experience with them waiting so long," she recalled. "I had no idea it would come so quickly, but it's been great."
However, she expected Season 3 to pick up the pace when she learned about the Caitlin-centric episode "Killer Frost." "I kept thinking that you would see Killer Frost earlier in Season 3. You know, we had that big episode, Episode 7, and then I felt like we kind of forgot about it for a little bit and so I'm excited to see what they have planned for Season 4," she added.
In the end, that worked out just fine for her, as she greatly enjoys playing both roles. "I like getting to do both! You know, Caitlin doesn't wear dark nail polish colors. Killer Frost definitely does wear dark nail polish colors. Getting to see the things that one character would do and one character wouldn't do and getting to do all of them and have fun with all the different levels has been great," she shared.
"It's so fun! I mean, you look at Tom Cavanagh, an unbelievable actor who's done such a fantastic job creating so many different characters on our show, and it's cool," she said. "It's fun to do and to find the different variations and that sort of thing. It was great. We had a field day."
She added that there's a distinction between Earth-1's Killer Frost and Earth-2's Killer Frost, who appeared for a few episodes in Season 2. Asked if there was a difference between them, she revealed, "100%. That is. It's very different. One of the things I'd like to see more of is to understand why Killer Frost is so evil and what her motivation is there."
She also praised her co-star Tom Felton, who played her love interest Julian Albert over the course of Season 3. "Tom is great! You know, what I honestly really liked about it was the struggle. You know, I feel like Caitlin had been quick to dive into some relationships in previous seasons, and the fact that she didn't immediately dive into the relationship with Julian I really liked," she explained. "I like that she was sort of honest with him and said, 'Look, I'm not really ready to be in a relationship.' Like, 'I have things that I need to deal with before I'm ready to be with someone and I'm afraid to be with someone.'" Though Felton's character became a part of Team Flash in Season 3 because of his interest in Caitlin, he will not return for Season 4.
As to her favorite twist on the show, she said, "I go back a lot of times to the scene in the elevator bay, where she looks at all those boys and she says, 'I never loved any of you.' It's heartbreaking, because we know she's lying. Is she trying to convince herself? Is she trying to convince them? Does she convince them? I think that was a nice moment to be a part of. I don't think it was nice for those characters."
Starring Grant Gustin as the Scarlet Speedster, The Flash returns Tuesday, October 10 at 8 p.m. ET/PT on The CW. The series also stars Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Candice Patton, Danielle Panabaker, Keiynan Lonsdale and more.