8th episode of the 4th season of Buffy the Vampire Slayer
"Pangs" is the eighth episode of season 4 of the television show Buffy the Vampire Slayer. It was written by Jane Espenson, directed by Michael Lange, and first broadcast on November 23, 1999 on The WB. On Thanksgiving, Buffy encounters the restless and vengeful spirit of a member of a fictionalized portrayal of the aboriginal Chumash tribe, who, in the show's setting, were wiped out by white settlers. During a tense confrontation, the Slayer fights a losing battle against her formidable foe - but a mysterious protector watches over her from the shadows. Buffy scholar Rhonda V.
https://en.wikipedia.org/wiki/Pangs