Werewolves were creatures that appeared human but tranformed into beasts in the light of a full moon. The bite of a werewolf would turn the victim into a werewolf. Like it happened to Queen Victoria when the Tenth Doctor met her.
Because they existed in myths, they were present in the Land of Fiction. The Cybermen converted them as woodsmen, but under the full moon they turned into monsters of plastic and flesh and fur. This showed the Cybermen the potential of converting other fictional creatures. (AUDIO: Legend of the Cybermen)
The universe was home to several types of werewolf.
Werewolves were apparently prevalent in pre-World War II Germany, where Emmeline Neuberger remembered being forcibly recruited by the government along with other werewolves as a death squad before she escaped to England, although she later reflected that her memories could have been altered by Hester Stanton. Emmeline helped the Eighth Doctor and Harry Sullivan prevent Hester's plan to take over the world, and may have turned Harry into a werewolf, but Harry was subsequently taken away by the Fourth Doctor and Sarah Jane Smith. The Eighth Doctor attempted to arrange help for Emmeline via his government contacts, but they held her prisoner to try and find a way to force the change until she was rescued by the Fourth Doctor (who would go back to rescue Harry in his future). During this time the Fourth Doctor learned how to force and reverse the change to trigger Emmeline's transformation and later turn her back, and it is possible that he was able to devise a permanent cure for Harry. (PROSE: Wolfsbane)
The First Doctor and Susan encountered a werewolf in 1963 and were put on trial after they killed it, forcing the Doctor's future selves to act as jurors to cast doubt on the case. (PROSE: The Juror's Story)
The Fifth Doctor and Turlough encountered Earth-based werewolves in 21st century Brazil, with these wolves so tied to Earth that they couldn't even ascend too high without being killed. (AUDIO: Loups-Garoux)
The Seventh Doctor and Ace met and befriended a Vulpanan werewolf named Mags in an era of space travel. Though good-natured, she had little control over her transformations. (TV: The Greatest Show in the Galaxy)
The Eighth Doctor, on a visit with Sam Jones to Saturnia Regina, encountered the Jax, a species thought extinct, who had in ancient times developed a virus controlled with technology that could turn people into werewolves. (PROSE: Kursaal)
Werewolf-like creatures Edit
On a distant planet, the Sixth Doctor and Charley discovered that the local creatures were essentially inverted werewolves, as they were wolf-like beings who turned into a primitive, feral humanoid in the day (AUDIO: The Red House).