"Kate Wilson" was the assumed identity of a member of the Committee, an organisation of aliens that took over planets. She was adopted by journalist George Wilson, and had to pretend to be a normal human through adolescence. When he started writing conspiracy theory books about aliens—her idea to start with, a joke, as she claimed—Kate fed him real facts about the Committee, snippets of true information presented as falsehoods. His books became wildly popular and she worked as his agent.
Meanwhile, she became a YouTube star by making videos discrediting his theories. When Sam Hallett started investigating Jack Harkness and Torchwood, Kate killed him in her hotel room, (AUDIO: The Conspiracy) room 111 at the Gabriel Hotel, (AUDIO: Cardiff Unknown - October 2018) and made his death look like a suicide. Jack realised Kate's identity and came to her hotel room, but she shot him, severing his spinal cord. While Jack was dying, she explained her role in her father's success, then shot him too. She left, leaving Jack to be found by the police. Jack came back to life and escaped. (AUDIO: The Conspiracy)
Kate escaped on one of Neil Redmond's planes to Stephenville, Newfoundland. (AUDIO: Uncanny Valley)