Sondra Bauer is a 'bitten' werewolf who appears in Stolen. Bauer joined forces with Tyrone Winsloe because she was obsessed with the power of supernatural races. She is turned after injecting herself with the saliva of Elena Michaels. She survives and is taken to the infirmary, where she briefly regains consciousness and later changes and kills Dr. Carmichael. Elena is forced to subdue her with the assistance of Xavier Reese and Bauer is moved into the cell next to hers. During the escape attempt, Bauer is shot and killed by one of the compound guards.
In "Dead Meat", She is first seen experimenting on Elena (who Alister had managed to capture earlier) and watches as Alister brands her with his bare hands. she then does more tests on Elena and informs her that she's a very important part of the undoing and needs to change into her wolf form in order for her to obtain her blood. she then performs an audio test on her in hope of forcing her to change but she doesn't and refuses to. Later she mixes Savannah's blood with Richard Hart [another werewolf] which results in the young witches blood cells to eat his. Bauer along with Alister doesn't want this to happen so he puts pressure on her to get Elena's blood and see what the results would be. she along with Alister then watches Elena as they have placed Elena in a small cage which opens up to a small battle arena. they then inform her of the situation [which is her having to transform to wolf form and fight Richard hart, another werewolf] and begin to countdown. they then open the door and release her into the arena with Richard [who wants revenge on her for betraying him and getting captured by Alister and his cult]. they then watch her [who's still in human form] surrender to Hart [who's in wolf form]. they then send in guards to restrain hart who they believe is about to kill her. unfortunately for them, Hart kills one guard and Elena subdues the other which results in the both of them escaping the compound and making a run for it into the forest; ultimately she fails and he is killed in the process. Later on, Bauer takes Elena's blood and mixes it with Savannah's but the results appear to be the same as before. she then draws up a large amount of Elena's blood into a needle as she plans on using it for something. finally she is seen in a ritual with Alister [who she is on top of and is naked] on the floor with the infinity alliance symbol on it and is surrounded by candles and followers who begin to chant as they watch. she then injects the needle into her thigh and begins to convulse [which is how the episode ends].
In "Rabbit Hole", it is revealed how she met Alister for she was working in a research lab in Abbott University where she experiments on animals as a two headed bunny is seen by two colleagues who walk into the lab (trying to hook up but are unaware that their not alone). they then inform the dean of the university who then fires Bauer and orders the animals to be destroyed. She then attempts suicide by jumping off the university's parking garage when suddenly a bunch of crows fly out of nowhere and knock her down which causes her ankle to break. Alister then appears and takes away her pain but she tells him she wants to feel pain. Back in the present; After Bauer injects herself with Elena's blood, Alister summons Elena to help her go through the change. As she goes through the symptoms, Elena shares her experience of going through the change. suddenly she stops to change just as she's about to start. She then tells Elena about Alister's plan which is to use her and Savannah's blood to kill all of the witches. Later on as Elena talks to Alister about his past and upbringing, Bauer has completed her change and is on the loose as she goes around the compound killing people in her sight. she then goes after Savannah Levine who Elena and Alister both hear scream. Elena then rescues the young witch while trying to talk some sense into Bauer. suddenly one of Alister's minions comes in and gets used by Elena as a shield against Bauer who kills him. eventually she makes her way back to the lab and turns back into a human. she is then greeted by Alister who realizes that she has become insane, babbling nonsense. Seeing that Bauer is of no further use to him, Alister then promises to give her a pain she's never felt before and kills her as he uses his powers to make her completely bleed out.
- She was portrayed by Carly Street