Buffy the Vampire Slayer: Potential

"Potential" is the twelfth episode of season seven of the supernatural/action series Buffy the Vampire Slayer and the 140th episode of the series overall. It was directed by Michael Gershman and written by Drew Goddard. It first aired on UPN on January 21st, 2003. In this episode, an insane priest named Caleb arrives in Sunnydale and tortures a potential Slayer. He instructs her to deliver a message to Buffy and the others. Faith returns to Sunnydale and gets into a fight Spike. Once explanations are made, the two enter into a very unlikely congress. Buffy gathers the Scobbies and tracks Caleb down. Xander suffers a serious injury at the hands of the deranged preacher.