Buffy and Joyce Summers move to Sunnydale. Buffy is a Vampire Slayer and was kicked out of her previous school because of her alter ego. At school she meets queen bitch Cordelia, geeky Xander, Jessie and Willow. She also meets the librarian and her new Watcher Giles. Beneath Sunnydale an old vampire called the Master is trying to rise again. A mysterious man warns Buffy that “The Harvest” is coming.

Buffy fights off Luke and saves Xander and Willow from being taken. Willow helps Buffy work out where the vampires are hiding and she heads back alone to the mausoleum. Angel warns her to be careful and Xander leaves school to join her. Jessie has been turned into a vampire and leads them into a trap from which they narrowly escape. Giles learns what the harvest is as the Master will attempt to break free and open the hell mouth. Joyce tells Buffy she can't go out but she does and heads to the Bronze. While she fights Luke, Giles and Willow help people escape. Xander tries to reason with Jessie but ends up killing him. Buffy kills Luke foiling the Master's escape plan.

Buffy tries out for cheerleading along with Willow's friend Amy. Neither makes the team but are alternates. One by one other cheerleaders are inflicted with horrible ailments leading Giles to conclude that someone is targeting them with witchcraft. Buffy suspects it is Amy and when Buffy herself falls victim to a spell she and Giles head out to confront Amy's mother. It turns out Amy's mother was so obsessed with reliving her youth that she switched bodies with Amy.

New teacher Miss French arrives and causes the men of Sunnydale to take notice. The teacher she replaced was killed and suspicion falls on a vampire who cut his own hand off and replaced it with blades like a fork. But while hunting him Buffy sees Miss French scare him away. Buffy and co work out that Miss French is a She-Mantis who mates with virgin men to breed and then kills them. While they search for her Xander and another boy Blayne are already locked up in her basement awaiting their fate.

Buffy gets a date with thoughtful hunk Owen but has to miss it when Giles uncovers an ancient Master-related prophecy which is about to take place. Nothing happens though and so the next night Buffy heads out on a date with Owen at the Bronze. Giles meanwhile follows up a lead at the funeral home. He is trapped there by vampires and Willow and Xander bring Buffy to him. Unfortunately Owen follows her and is knocked out as she kills a vampire. The next day she breaks up with him realising that his life would be in danger if she kept seeing him. Meanwhile unbeknownst to Giles the prophesy is fulfilled anyway.

On a field trip to the zoo Xander and a gang of cool kids get possessed by hyenas. Slowly Xander rejects Willow and Buffy to join them in their cruelty to others. They eat the school mascot (a pig) and then Principal Flutie while Xander molests Buffy. She manages to lure them back to the zoo where Giles arranges with the zoo keeper to try and reverse the possession.

The Master sends "The Three" against Buffy and Angel helps her survive. To be safe he hides in her room and eventually they kiss. But as they do she discovers that he is a vampire and he flees. We learn that Darla made him a vampire and for over a century he caused murder and chaos like all vampires. But he was cursed by a gypsy tribe who restored his soul. Since coming to America he hasn't fed off humans and now Darla wants to bring him back into the fold. Darla bites Joyce and frames Angel making Buffy determined to kill him. However Angel kills Darla instead, tells Buffy the truth and she lets him live.

In 1418 the Demon Moloch is trapped in a book. In the present day Willow scans the contents of the book into the library computer and Moloch is released into cyber space. He begins to seduce followers who do his bidding. At the same time Willow has a new online boyfriend Malcolm. Buffy is worried by Willow's obsession with a guy she has never met. Computer teacher Miss Calendar spots the empty book which alerts Giles to Moloch's escape. When Willow is taken by Moloch's followers Buffy and Xander try to free her while Giles and Miss Calendar try to cast a new spell.

New school principal Mr Snyder puts Giles in charge of the annual talent show. To their horror he then insists that Buffy, Xander and Willow join in too. A girl is killed in the locker rooms and her heart is cut out. Suspicion falls on Morgan and his dummy Sid who seem a little too convincing an act. Giles looks into the alternative explanation: demons who harvest organs to maintain a human appearance. When Morgan is found dead Buffy confronts Sid who turns out to be a demon hunter and they try to discover who the real killer is before he takes anyone else's brain.

Students nightmares start coming true and Buffy keeps seeing a mysterious young boy. She and Giles discover that he is a local boy, Billy, who was beaten into a coma after a kiddy league game. Now it seems that his nightmares and everyone else's in Sunnydale are coming true. Giles gets lost in the library and then forgets how to read. Xander walks into class naked and is then attacked by a clown. Buffy's Dad swings by to tell her that she was responsible for her parents splitting up. Then she is buries alive by the Master and turned into a vampire. Finally she helps Billy overcome the "Ugly Man" who has been tormenting him and he wakes from his coma.

Those close to Cordelia are being attacked by an invisible force. Buffy and company work out that it is one of their missing classmates Marcie. The world paid her so little attention that she turned invisible and has gone mad. Cordelia comes to Buffy for help while Angel comes to talk to Giles about some prophecies. Marcie's jealousy of Cordelia's popularity leads her to attempt to permanently disfigure her.

Xander asks Buffy out and she rejects him. Giles reads the prophecy that as the Master rises, the Slayer will die. Buffy overhears him discussing this with Angel and says she quits being a Slayer. However other vampires are gathering around the hellmouth in anticipation of the coming apocalypse and kill a bunch of students. Buffy realises that she must face the Master and follows the Anointed One down into the church to meet her fate. Xander and Angel follow after her.