The Flash Season 5: 6 Major Questions We Have For The Second Half
5. Can Caitlin Save Her Father From The Icicle?
Earlier in the season, Caitlin Snow discovered that, after spending years thinking that he had succumbed to ALS, her father Thomas was actually alive. Tracking him down to an abandoned Tannhauser facility, she had a heartfelt reunion with him. However, all was not as it seemed, as this entity wasn't actually her father - it was his cold-hearted alter-ego, The Icicle.
Through a passionately deceiving performance, the icy villain almost tricked everyone into engineering a serum that would allow him to take complete control of Thomas' body, silencing Caitlin's father for good. However, thanks to Cisco, Caitlin soon saw things clearly and the mere thought of losing her dad to this monster forced her to finally break through her mental block, and channel her dormant other-half. In doing so, Killer Frost finally returned and saved the team - destroying the serum in the process.
Though The Icicle managed to escape, it's highly unlikely that we've seen the last of him. Killer Frost is becoming more and more significant to the overall narrative this season and, as Caitlin's hunt for her father played such a major role in the first half, we should expect it to come up again at some point in the back half of the season.