Faith Lehane

In Buffy the Vampire Slayer season 3, Faith arrives in Sunnydale, having been activated as the Slayer by Kendra's death in the episode "Becoming, Part One". Coming from a traumatic and abusive background, Faith tries to fit in with Buffy and her friends, but becomes increasingly isolated and bitter as the season progresses. A major turning point for the character occurs in the mid-season episode "Bad Girls"; while trying to show Buffy the fun side of slaying, Faith accidentally kills Deputy Mayor Allan Finch, a human being whom she mistakes for a vampire. Feeling more alienated than ever, she betrays the Scooby Gang and allies herself with the villainous Mayor of Sunnydale, eventually forming a sincere father-daughter relationship with him. After Faith tries to murder Buffy's vampire lover Angel under the Mayor's orders, the two Slayers finally battle it out in the season finale, a confrontation which leaves Faith alive but comatose.

Faith returns to Buffy for two episodes in the 4th season. Waking up from her coma, she seeks revenge on Buffy by switching their bodies using a mystical device called the Draconian Katra left to her by the now-deceased Mayor. As Buffy is taken into custody by the Watchers' Council for crimes she did not commit, Faith discovers for the first time what it is like to be surrounded by loving friends and family, and Buffy starts to understand Faith despite being upset with her predicament. After feeling obligated to rescue a church full of people from vampires, Faith battles Buffy once again, expressing extreme self-hatred before being returned to her own body. The storyline is continued in the 1st season of spin-off series Angel, as Faith escapes to Los Angeles and is hired by Wolfram & Hart to assassinate Angel. Instead, she plots an intricate plan to have Angel kill her, but Angel convinces her to face the consequences of her actions, and helps her on the path to redemption. Faith hands herself over to the police and she is sentenced to a women's prison, where Angel later visits her.

In Angel season 4, Angel is reverted to the evil Angelus after having his soul removed. Faith is approached by her former Watcher, Wesley Wyndam-Pryce, who informs her of Angelus's presence, sparking her to break out of prison and help them. Wanting to help Angel the way he helped her, Faith injects herself with a mystical drug and feeds herself to Angelus in order to incapacitate him. She nearly dies from the drug, but during a psychic mind walk, Angel persuades her subconscious not to give up and that life is worth living.

Afterwards, a recovered Faith travels back to Sunnydale, where she plays a significant role in the battle against the First Evil in the final season of Buffy the Vampire Slayer. In these episodes, she reconciles with Buffy, although their relationship is tested when the Potential Slayers appoint Faith as their leader over Buffy. This decision later proves disastrous when Faith's plan leads them into a trap, leaving several girls dead. She and the survivors are saved by Buffy, and the two finally make peace with one another. After a one-night-stand together, Faith begins a romantic relationship with school principal Robin Wood when they both survive the battle in the series finale.

Faith was set to receive her own spin-off following the end of Buffy, which, according to Tim Minear, would have featured Faith "probably on a motorcycle, crossing the Earth, trying to find her place in the world." However, Eliza Dushku had other commitments so the series never materialized.

The character of Faith is expanded upon in media outside of the television series, such as the Buffy Season Eight comic book.

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