Overview
"Graduation Day" is the season finale of the third season of the drama television series Buffy the Vampire Slayer, consisting of the twenty-first and twenty-second episodes. They were written and directed by series creator Joss Whedon. "Part 1" first aired on May 18, 1999 and "Part 2" first aired on July 13, 1999; both airing on The WB. The second part was to originally be aired on May 25, 1999, but was postponed due to the episode's content and the occurrence of the Columbine High School shootings one month prior.
The episodes are the last to feature David Boreanaz and Charisma Carpenter as series regulars due to their starring in the spin-off series Angel.
Plot
Part 1
Faith kills Professor Worth on the Mayor's orders, causing Buffy and Giles to investigate. Anya reveals that she has previously seen an Ascension, explaining that the resulting demon will be much stronger than anything the group has faced. The Mayor interrupts the meeting, threatening the group. Giles stabs him, but the Mayor is unharmed. Buffy convinces Joyce to leave town for her own safety. Willow searches desperately for a spell to stop the Ascension, but finds nothing. Oz calms her down with a kiss, and they have sex. Angel and Buffy raid Worth's office, finding some notes which they take to Wesley and Giles, who discover that Worth had found the bones of the demon Olvikan. Faith shoots Angel with an arrow laced with a toxin deadly to vampires, leaving Angel near death. The Watchers' Council refuses to help Angel, leading Buffy to quit the Council. Willow learns that a cure requiring the blood of a Slayer exists. The Mayor eats some insects from the Box of Gavrok, part of his preparation for the Ascension. Buffy finds Faith at her apartment and the two fight. Buffy stabs Faith, but she jumps off into a passing truck.
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