Reinforcing that Sav's identity ties into why KF falls in line so quickly

"Unfortunately for Barry (Grant Gustin) & Co., Killer Frost also subsequently and swiftly aligned with Savitar upon learning the speedster’s identity during last week’s episode. “There’s a relationship that exists there that prompts Killer Frost to turn her loyalty to Savitar very quickly,” Panabaker teases. “Once it becomes clear who Savitar is, you start to understand why Killer Frost aligned with him so quickly. Killer Frost’s quick alignment with Savitar informs a lot of the decisions that she makes.”"