Fed up with life as a mortal, Anyanka begs a demon named D'Hoffryn to create a temporal fold that would allow her to retrieve her powercenter -- the necklace she wore around her neck -- before it was destroyed. D'Hoffryn has no interest in helping Anyanka and would rather see her live out the rest of her life as a mortal. Anyanka pledges to find someone who will help her. Outside of Sunnydale High, Willow hones her pencil-floating skills while Buffy prepares for a traditional Slayer evaluation which Wesley is conducting. Later, Willow is called to Principal Snyder's office, where another student named Percy West is also waiting. Percy is one of the star members of Sunnydale High's basketball team who just so happens to be having trouble in history class. Principal Snyder orders Willow to tutor Percy. Afterwards, Willow and Buffy go to the library. While Willow heeds Giles' request to try to access the Mayor's computer files, Faith returns with Wesley from the physical portion of the tests. Faith takes note of Willow's computer search, and she later reports it to Mayor Wilkins himself during a tour of Faith's new apartment. Decked out with nearly everything she could ever want, the apartment leaves Faith absolutely giddy. Back at Sunnydale High, Willow learns that Oz and his band just returned from an out-of-town gig. Willow tells Oz that she may have wanted to go. Oz replies with the expectation that Willow wouldn't have wanted to miss a school day. Spotting Percy, Willow tries to arrange a meeting time for their tutor session. However, Percy has a different game plan which involves Willow doing all of the work for him. The last straw for Willow comes when Buffy comments on her reliability. Tired of being the goody-two-shoes of the group, Willow stalks off by herself. She runs into Anyanka, who introduces herself as Anya, a friend of Cordelia's. Willow's mood takes a turn for the lighter when Anya asks for her help in performing a spell to create a temporal fold. Anya explains that she wants to retrieve a lost necklace which was a family heirloom. When Willow and Anya perform the spell, Willow sees visions of the alternate universe that Cordelia visited when she told Anya that she wished Buffy had never come to Sunnydale. Something goes wrong in the course of the spell. Instead of pulling the necklace out of the alternate universe, the vampire Willow is transported out just moments before Oz could dust her on the jagged wood. While Anya futilely searches for the necklace, Willow leaves her alone to try and figure out what she just saw. Elsewhere, the Willow from the alternate reality awakens. After night falls, she ventures out onto the streets of Sunnydale. Quickly realizing the vast differences surrounding her, Alterna-Willow heads to the Bronze. There, she draws stares from everybody in attendance, including Percy West. Provoked by Percy's arrogance, Alterna-Willow shoves him over the pool table, then grabs him by the throat and tightens her  grip. Xander pulls Percy away before noticing Willow's radical makeover. Thinking he's the Xander of her reality, Alterna-Willow pulls him into her arms, running her hands all over his body. It doesn't take long for her to realize that Xander is still a living, breathing human. Buffy arrives and can't believe her eyes when she sees Willow. When Alterna-Willow recognizes Buffy as the Slayer who staked her beloved Xander, she turns and heads for the Bronze's exit. Buffy tries to stop her, but Willow spins around with vamp face on. She then takes off, leaving Xander and Buffy horrified and speechless. Outside the Bronze, Alterna-Willow encounters two of Mayor Wilkins' vampire henchmen, one of whom is named Alfonse. With the help of a little sadistic brutality, Alterna-Willow convinces the vampires to work for her and restore chaos to Sunnydale. Giles gets the word on Willow's untimely death from Buffy and Xander. During their lament over the loss of their friend, the Willow of their reality enters the library. Simultaneously confused and happy, Buffy, Xander, and Giles embrace Willow, who by this point is simply confused. While they tell Willow about her evil twin, Angel enters the Bronze in search of Buffy. As he talks to Oz, Alterna-Willow and her newly-hired cohorts invade the Bronze. After Angel leaves to get Buffy, Alterna-Willow kills and drinks from one of the customers. Oz tries to make sense of what's going on, but Alterna-Willow only remembers him as one of the human rebels from her reality. Anya clears up everything for the lost vampire, telling her that the Willow of this reality is the only one who can bring her back to where she  belongs. Meanwhile, Angel reaches the library and walks right up to Buffy, Xander, and Giles. He doesn't notice Willow standing in the corner as he tells the gang that their friend is dead. Willow makes her presence known, sending Angel into the pits of confusion as well. Realizing they have to stop whatever's about to go down at the Bronze, the group leaves the library. Willow, however, is reluctant to kill her alter ago. Remembering the tranquilizer gun, Willow tells the others to go ahead while she heads back into the library. Before she can get the gun, Willow encounters her mirror image, who has sneaked into the library unnoticed. Intrigued by the idea of occupying a world with her double, Alterna-Willow gets uncomfortably cozy with Willow, who retaliates with a cross. Alterna-Willow knocks her over the counter. When the vampire circles around the counter, she is greeted by a tranquilizer dart right in the stomach. Buffy and the gang return and lock Alterna-Willow inside the bookcage. Buffy then comes up with a plan to take care of the vampires in the Bronze. Disguised in the outfit of her other self, Willow prepares to infiltrate the Bronze and trick the vampires into walking outside, one by one, and getting staked by her friends waiting outside. As Willow enters the Bronze, Alterna-Willow wakes up in her prison. While she notices her own change of clothes, Cordelia enters the library. Alterna-Willow tries to talk her into opening the cage, but Cordy opts to use this opportunity to talk about the secret affair with Xander. After an eternity of rambling, Cordy finally opens the cage. Hungry for blood, Alterna-Willow chases Cordy through the halls before cornering her in a restroom. Before the vampire can close in for the kill, Wesley appears and fends her off with a cross and holy water. Thwarted, Alterna-Willow turns around and leaves. Meanwhile, Anya and Alfonse eventually see through Willow's charade. Willow screams, signaling the others to storm into the Bronze and battle the remaining vampires inside. During the fight, Alterna-Willow arrives and pins Willow on the stage. After dusting Alfonse, Buffy leaps onto the stage and drives a pool cue towards the vampire's heart. Willow screams for Buffy to stop, and the Slayer is able to halt her weapon's descent. After all of the customers evacuate the Bronze, Alterna-Willow and Anya prepare for another temporal fold. Buffy does not agree with the idea of returning a demon to its own reality where it can kill again. Willow responds by saying that she simply can't kill her. Before Willow sits down to perform the ritual, she says her goodbyes to Alterna-Willow, who says hers in a much more touchy-feely way. Afterwards, Alterna-Willow is returned to the alternate reality... only to be grabbed by Oz and dusted on the jagged wood. The next day, Willow contemplates living up to her good girl reputation and never going out for fun again. When Percy appears with the history paper completely typed out, Willow decides otherwise.