'The Flash' Star on Firestorm Surprise: Caitlin Is “Freaked Out"

Danielle Panabaker says she goes on a "secret mission" in the midseason finale
Jack Rowand/The CW

Things are really heating up for Caitlin (Danielle Panabaker) on The CW's The Flash.

In Tuesday's midseason finale, the S.T.A.R. labs genius begins to think she is seeing her (dead?) fiance Ronnie (Robbie Amell) — and understandably is a little freaked out. So she enlists Cisco (Carlos Valdes) to help her figure out what's going on. (As we know from casting news, Ronnie is destined to become one-half of Firestorm.)

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"Caitlin and Cisco are on a secret mission and they don't tell Dr. Wells (Tom Cavanagh) about it, but they can't keep that secret for long," Panabaker tells The Hollywood Reporter.

In a chat with THR, Panabaker teases the "incredible episodes" ahead, weighs in on if Wells is good or bad and addresses Barry's (Grant Gustin) search for his mother's killer.

What is Caitlin up to in this episode?

In our midseason finale, she thinks she's seeing Ronnie. As most people would react if they think they are seeing their dead fiance, she's a little freaked out at first. But she has Cisco to help her, and they start trying to find out what really happened to Ronnie in the particle accelerator explosion.

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This sounds like it could be your most important episode yet.

It's putting Caitlin in motion for some really incredible episodes to follow.

What was the best part about preparing for this episode?

We've teased the Ronnie relationship since the pilot. It's nice to see what happens next. That storyline obviously isn't over. It's really exciting as a viewer to see what's going on with Ronnie and what happens next.

Caitlin and Cisco add a  charming element to The Flash. What's working with Carlos like?

Caitlin has such a great relationship with Cisco and it is very sibling-like. I love Carlos and think he's so talented. As an actor it's a fun dynamic to play with. Our characters have such opposite energy, that putting us on screen together and even the looks we give each other is a lot of fun.

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Is this Ronnie stuff related to Reverse-Flash?

In Central City, you are constantly surprised by the way people were affected by the particle accelerator explosion, and how people come into contact with each other and how their powers develop. Caitlin and Cisco are on a secret mission and they don't tell Dr. Wells about it, but they cant' keep that secret for long.

In Caitlin's mind, is Dr. Wells good or bad?

Absolutely good. The reason she came back to S.T.A.R. Labs after the explosion was her faith in him. She's probably going to be one of the last people who is skeptical of Dr. Wells' intentions.

When you watch the show, how much do you know ahead of time?

I am constantly surprised when I watch the show. So much is done in postproduction, it's so exciting to see what they are doing. It's so fun for me because I get to enjoy the show with the audience. 

Email: Aaron.Couch@THR.com
Twitter: @AaronCouch