Celia Soames
Celia Soames was looking for a vampire in Budapest in 1980, believing that it was Count Dracula. She spotted the Fourth Doctor over a vampire's victim and assumed that he was vampire. She described herself as a professional vampire hunter. She went with the Doctor to the labyrinth under Buda Castle.
When attacked by the now vampiric Anita Kereki, she stabbed her with a stake in the lower back. She wanted to become a vampire queen of Zoltán Frid and was his human agent. The Doctor told her that all she was doing was giving Frid the power to kill her. She knew that Frid would kill her so she and the Doctor put a hypnotic suggestion which got made anyone who heard the phrase "sunbathing" want to walk into the sun. (AUDIO: The Labyrinth of Buda Castle)