[Warning: The following contains spoilers from Tuesday's episode of The Flash. Read at your own risk!]
The closing scene of Tuesday's episode showed Caitlin accidentally icing her shower, growing a white streak of hair and dawning a pair of blue lips, but as of now there have still been no changes to her behavior to indicate that she's crossing over to the dark side like her Earth-2 doppleganger from last season.
Yet Caitlin seems determined to keep her abilities a secret from Team Flash. Earlier in the episode, she had to use her powers to free Barry (Grant Gustin) from a mirror trap, but did it in secret so that no one from the team would realize what she had done. The question is, why?
We know that all of the Zoom (Teddy Sears) events occurred last season, but due to Team Flash's unanimous decision to not discuss the differences in the current timeline versus Barry's "Flashpoint" timeline, we can't be 100-percent sure that the team encountered Killer Frost as well or that Caitlin knows the full extent of her doppleganger's powers.
Even if Killer Frost did encounter Team Flash in the revised timeline, that isn't enough to say that Caitlin manifesting similar powers means that she'll also turn into a killer meta-human. So far, her powers have only been used for good and there's been no change in Caitlin's disposition on the team. It's entirely possible that these powers could come to fruition and Caitlin remains the same kind scientist that we've known for two seasons now. The powers could take her out of the lab and make her an integral part of Barry's crimefighting team. If Captain Cold (Wentworth Miller) is going to be spending his time in the Legion of Doom on Legends of Tomorrow, Caitlin could make a great frosty counterpart to Barry's lightning speed.
There's no evidence yet to explain why Caitlin is so freaked out by her powers. They didn't manifest like Cisco's (Carlos Valdes) did, with the traumatic memory of having his heart slashed into pieces by the Reverse Flash (Tom Cavanagh). In fact, all Caitlin (possibly) knows about Killer Frost are the stories that Barry told her when he and Cisco returned from Earth-2 last season.
If she really wants to figure out what's going on with her, and if there's a real chance that she'll turn evil, Caitlin needs to stop hiding in the shadows and come clean to her team about what's happening with her. Who better to help than the brilliant team of S.T.A.R. Labs? Plus, has Team Flash not learned that there's no secret that doesn't eventually come to light?
The Flash airs Tuesdays at 8/7c on the CW.
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