|First Appearance||How it all began|
|Series lifespan||Season 1 to ???|
Before the crashEdit
On the RunEdit
Katie worked on Ray Mullen's farm in Australia and was planning to subsequently travel to Bali, but Mullen discovered her wanted poster at the post office, and attempted to turn her in to Sean Davidson. Katie realised the plan, but when her escape attempt endangered Mullen's life, she chose to save him rather than escape. Davidson consequently captured Katie and prepared to extradite her to the U.S. aboard Fusion Flight 220.
Fusion Flight 220Edit
On the plane, Sean Davidson taunted Katie. During the flight's turbulence, luggage flew from the overhead luggage bin and rammed into Davidsons' forehead and knocked him out. Katie stole his keys and unlocked her handcuffs and then placed the oxygen mask on his face, remaining conscious throughout the entire crash.
On the IslandEdit
Paul Murphy noticed Katie walking out of the jungle and asked her to stitch up his wound, to which she agreed reluctantly. Later that night, they introduced themselves to each other properly. During her second day on the Island, Katie, Daniel Lafferty and Oisin Neary went on a mission to retrieve the cockpit's transceiver from the plane debris. They tried to rescue the injured The Pilot, but The Monster attacked them for the first time. When they returned, Paul Murphy repaired the transceiver. To receive a signal, Katie, Paul and several other survivors hiked to higher ground of the Island. During their journey, Brian Marshall killed an attacking polar bear with the Marshal's gun. Katie removed it from his possession, but she feigned inexperience with the weapon. Eventually, the transceiver picked up a chilling distress signal.
Back at the camp, Katie visited the injured Marshal. He attacked her, further straining his injuries. Katie told Paul that he should euthanize the dying man, but Paul questioned her true motives because he had learned about her criminal record. She returned the gun to Kevin, who agreed to end the Marshal's life. Katie offered to tell Paul why she had been arrested, but Paul said that all the survivors deserved a fresh start.