Dawn finds vengeful spirits in the new Sunnydale High; Giles is rehabilitating Willow in England. Spike is living in the high school basement and going insane after being filled with guilt upon the return of his soul.
The gang deals with a giant underground demon; Willow prepares to return home. Spike reveals to Buffy that he has regained his soul.
A weak and vulnerable Willow returns home but cannot find her friends in Sunnydale. At the same time, they cannot find her, but bodies are being found without skin, and the resemblance to Willow's murder of Warren alarms Buffy and Xander.
Buffy becomes a counselor at Sunnydale High and meets a girl who predicts her own death. Buffy learns that sometimes, whatever you do, you can't always stop bad things from happening.
Buffy deals with Anyanka after she grants a lethal wish; Anya's background story is also revealed. The two end up fighting, with Xander unsure of where his loyalties lie.
Dawn, Buffy, Willow and Anya fall in love with a high school quarterback as a result of a 'magic' jacket. Xander and Spike become reluctant roommates, but try to sort out the confusion.
Buffy talks through her troubles with an old high school classmate who has recently become a vampire. Cassie, the late student Buffy tried to help, appears to Willow with a posthumous message from Tara. Dawn experiences a terrifying haunting. And Andrew and Jonathan return to Sunnydale High on a mission.
Buffy and her friends fear Spike may be to blame when a number of people around town mysteriously disappear.
The Summers' home gains two captives: Spike and Andrew. The Watchers Council is attacked directly by an agent of the First.
Giles returns to Sunnydale with three potential slayers, whom Buffy must protect from The First. Meanwhile, a ferocious Uber-vampire is released from the Hellmouth and Buffy must kill it before it kills one of the potentials.
Buffy has to keep the ever increasing number of potential Slayers from panicking while Giles and Anya seek answers from the Beljoxa's Eye.
Buffy and Spike establish a boot camp to prepare the Potential Slayers for combat, while a spell from Willow reveals another Potential in Sunnydale. Dawn thinks it may be her for a short while, but then the true Potential is revealed.
After sharing a lingering kiss with would-be Slayer Kennedy, Willow bafflingly transforms into Warren and must confront the loss of Tara. When Spike's chip begins to malfunction, he and Buffy take a trip to the Initiative stomping grounds, where they meet up with a few remaining soldiers who give her a choice of how to deal with the problem. Meanwhile, when Giles takes the Potentials on a self discovery quest, the rest of the gang find clues that lead them to believe Giles may be the First Evil.
Buffy accepts a dinner invitation from Principal Wood, and tries to figure out his true intentions. Xander goes out with a girl from the hardware store. The First tries to convince Andrew to murder the potential Slayers. Giles returns from China with a new Potential, but struggles with the language barrier.
Buffy introduces Principal Wood to the rest of the team. He brings an artifact that transports Buffy to see the origin of the Slayer, but the others must face a powerful demon to bring her back.
Andrew creates a documentary called "Buffy, Slayer of the Vampyres", a record of the current situation in Sunnydale to show to future generations. He manages to capture many important moments, and to annoy almost everyone in the house. But Buffy needs to tear him away from his filmmaking because the Seal of Danzalthar is active and Andrew may hold the key to closing it before it destroys the town.
The gang investigates Spike's trigger; Principal Wood and Giles decide to eliminate Spike without Buffy's knowledge or approval, but fail. Buffy confronts them.
Faith returns to Sunnydale; a new powerful evil face appears, Caleb, a former priest who is unstoppable and works for the First; Buffy leads the troops into battle. Xander loses his eye to Caleb and some of the Potentials are killed by him.
As the residents of Sunnydale evacuate, and the Potentials suffer many casualties, Buffy loses the trust of the group and is forced out of the house. Faith becomes the leader.
A depressed Buffy is comforted by Spike; Willow and Kennedy become intimate, as do Faith and Principal Wood. Anya and Xander rekindle their spark. The Scoobies capture and interrogate a Bringer; Faith decides on a plan, but it doesn't go smoothly.
Buffy has a powerful new weapon, but the gang cannot find any information about the origins of the mysterious scythe. Eventually the Slayer goes herself in search of knowledge, and finds a new ally, an old friend, and great danger.
Buffy talks to Angel about the future. Buffy and the Scooby Gang devise a plan to launch an all-out assault against the First. They all descend on the Hellmouth, as Willow uses a spell on the Scythe to turn the Potential Slayers into actual Slayers and they engage in a vicious battle against thousands of Ubervamps. Spike uses the amulet Angel brought from L.A. and brings about the end of Sunnydale, and the Hellmouth. Buffy is able to escape the crumbling Hellmouth and reunites with the gang.