Jane Livingston (Judy Reyes) was the villainess from Medium episode 7.07, "Native Tongue" (airdate November 5, 2010). She is a linguistics professor who Allison DuBois bonded with due to her visions of the murder of a man in a trailer causing Allison not to understand English, and only understand the Navajo language, which Jane was speaking when they first met.
Allison's visions revealed that the murdered man was part of a bank robbery, and his partner was killed later in the episode. The last vision revealed that Jane had a role in the killings, as she and her boyfriend (who committed the murders) were looking for the stolen money. In the vision, Jane asks her boyfriend if he found out where the money was.
In the last scenes, the evil Jane contacted Allison, who now understands English again, and thanked her for warning her about her boyfriend killing her. With that knowledge, Jane killed her boyfriend/accomplice, and left on a tropical paradise, which is where Jane was calling from. Jane boasted to Allison about her misdeeds and now having loads of money, but her conversation is overheard by a man at a marketplace, who kills Jane for the money in the final scene of the episode.