Warning: spoilers ahead for Episode 6 of The Flash Season 5, aptly-titled "The Icicle Cometh."
The Flash spent years spinning the story that Caitlin's dad long before the series even began due to multiple sclerosis. She recently learned that her father's death was actually faked. Thomas Snow was alive, and he left clues for Caitlin to find him. Well, in "The Icicle Cometh," Caitlin finally found her dad, but their reunion wasn't everything she hoped and dreamed, and Thomas was gone again by the end of the hour. Poor Caitlin!
I spoke with Danielle Panabaker at the red carpet for The Flash's upcoming 100th episode, and she had this to say about Caitlin's father and his role in the show:
We knew that Thomas Snow was going to appear in Season 5 thanks to news over the summer that Kyle Secor of Veronica Mars had been cast to play Caitlin's dad. What we didn't know was the Thomas Snow would have a Killer Frost-esque personality of his own, going by the name of Icicle. Unfortunately, Caitlin didn't know about her dad's Icicle identity until a very inopportune moment, and he ultimately used his icy powers to blast off and away from Team Flash. He was alive but gone.
According to Danielle Panabaker, "The Icicle Cometh" is probably not the last we'll see of Thomas Snow/Icicle, and the storyline is open for him to come back. Honestly, the way his arc ended in his first episode, the stage is perfectly set for him to turn up once more. He could certainly return, and Caitlin could perhaps get some closure on the situation with her father. After all, the episode that revealed the villain Icicle also revealed that Thomas Snow is still alive and loves his daughter.
The good news for Caitlin is that she finally received some answers about how she became Killer Frost as a child and without the dark matter of the particle accelerator or The Thinker's tricks. Apparently, Thomas really did have a disease, and he was determined to find a way to stop its progression to prevent Caitlin from suffering the same ALS effects.
Thomas experimented on himself before trying out the technology on Caitlin, and it did work on both of them to the extent that neither is currently struggling with ALS. The unintended consequence of freezing the disease progression was that both Snows developed an icy side that came with an alternate personality with considerably less restraint.
While Caitlin found a way to coexist with her Killer Frost identity without losing either half, Thomas was not so successful. His Icicle side was dominant and cunning enough to trick Caitlin into helping him. When she discovered that he suffered from a disease that could have killed him, she developed a way to save his life.
Unfortunately, she later discovered that Icicle was using her to develop a treatment that would allow him to permanently suppress his Thomas Snow side, which would have effectively killed what was left of her father within Icicle. The good news is that Caitlin and Team Flash figured out what he was up to in time to stop him, although he did escape. Caitlin doesn't have him on hand to try and restore her father, but she doesn't have to worry that Icicle will be able to get rid of her dad entirely.
Icicle spent years waiting for Caitlin so that she could figure out how to get rid of his non-meta side, unable to make the breakthrough himself. Even the assistance of other scientists from afar (including a certain somebody by the name of Victor Fries) didn't help him figure it out. Icicle needs Caitlin to get rid of Thomas, and Caitlin certainly won't help him out with that.
Although Caitlin was devastated by what happened to her father, she did get some good news. Her efforts to stop Icicle before he froze her friends to death resulted in her Killer Frost side emerging again, and she was able to save the day with Killer Frost's icy powers.
Barry and Cisco eventually figured out that The Thinker hadn't used Melting Point's powers and removed Killer Frost from Caitlin's DNA; rather, he used Brainstorm's powers and created a mental block powerful enough to cut Caitlin's two sides off from each other. All Caitlin needs to do now is figure out how to take down the mental block permanently.
Cisco figured out a way to help her at least communicate with Killer Frost, even if she can't transform at will just yet. He dug out Harry's old mental activity dampener, and Caitlin realized that she'd be able to mentally talk to her other side with its help. Was this episode enough to permanently bring Killer Frost back and send Caitlin into the field on a regular basis? No. But it's a step in the right direction.
Given that Cicada has been taking down metas all over Central City and defeated Team Flash more than once already, Team Flash needs all the boots on the ground they can get. If Caitlin can recover her Killer Frost side entirely, she could be key to the fight against Cicada. After all, Cicada may not realize that she's a threat if she suddenly shows up with powers. Could Caitlin be the variable Team Flash needs to surprise Cicada?
We'll have to wait and see. For now, we can only cross our fingers that Caitlin figures out how to bring back her Killer Frost identity without the mental activity dampener. She clearly felt lost after losing Killer Frost; now that she suffered a major blow with the loss of her father and discovery of Icicle, she can use all the good news she can get.
Tune in to The CW on Tuesdays at 8 p.m. ET for new episodes of The Flash. The rest of 2018 promises to be exciting for The Flash, what with the upcoming 100th episode and the big "Elseworlds" crossover. For some viewing options once The Flash goes on its winter hiatus, swing by our midseason TV premiere schedule.