"Antonia Bailey" was the assumed name of a Shinx named Lyria. She was married to Gregory Bailey, whom the Sixth Doctor found murdered in Manchester on 28 February 2008. Both Lyria and her husband were living on Earth, disguised as humans.
Lyria was actually the facilitator of her husband's death, due to the staunch policy on divorce held by Shinx. She and her boyfriend Sam worked together to kill him, but this went wrong when Sam opened Gregory's case, in actuality an experimental device of Robert Slater's, merging him with the building. She later killed Slater at Sam's request, to make up for having asked him to commit murder. (AUDIO: The Condemned)