She originally lived in a colony world, when after some time, she and her family got "caught up in a war." Amanda Steele rescued them and so as thanks, Phelan offered her services to Amanda, becoming part of her team.
She and her team were hired by Georgia Donnelly, owner of Funworld after the skeleton crew of Funworld had suddenly ceased communication following a message talking about a "predator." This predator turned out to be the Vashta Nerada who had wiped out the entire skeleton crew. She and her team, alongside with Georgia, met the Fourth Doctor on Funworld. They discovered the truth of what had happened after Phelan created a psychic link between her and the Vashta Nerada.