While visiting the planet Világ and helping repel an alien invasion by an aggressive humanoid canid species known as the Killorans, Evelyn met and fell in love with Governor Rossiter, who eventually became the political head of the union of three nations ("Arrangements for War", 2004). When she and the Doctor returned a year later, Evelyn decided to stay and marry Rossiter. She subsequently became involved in the politics of Világ and underwent surgery for her heart. The surgery, however, did not correct her heart condition; without her knowledge, she was injected with blood extracted from Killoran prisoners. The infusion disguised Evelyn's heart condition but also caused her to suffer from headaches, increased aggressiveness, and irritability.