Tanya Wells is a villainess from Diagnosis Murder, appearing in Season Four's "Murder by the Busload."
She was played by Kathy Evison.
Tanya Wells is a paramedic and up-and-coming doctor at Community General Hospital, but her backstory revealed that she was sexually assaulted by serial rapist Fred Talisker. Because he was never brought to justice, Tanya sought revenge on Talisker, and during a bus accident, Tanya spotted Talisker on the bus and killed him, doing with a brick to his head. She was actually spotted by one of the living victims of the bus accident, a homeless man named Lou Kupfer, who attempted to point out Tanya as a killer while she brought him in.
Later in the episode, while Mark Sloan and the others searching for the killer, the evil Tanya appeared in Lou's room and killed him, doing so to keep her villainous secret hidden. Tanya ends up caught and arrested for both murders, but not before describing her anguish over her assault.