The Bronze is packed and Oz and the Dingoes are playing on stage. After a song wraps, Oz goes to stand by his friends and Willow and Xander act all jumpy. They discuss briefly the idea of Buffy and a new boyfriend, but Buffy lets them know she is seeing someone â Faith â but just as friends. The two go out and slay, finally killing two vampires. A new woman, who later identifies herself as Mrs. Gwendolyn Post, Faith's new watcher, doesn't appreciate the "sloppy" synchronized slaying.
That night, Post tells the Slayers and Giles that she was sent down to take over as Faith's watcher and report back on the entire situation in Sunnydale, including Giles, who she claims has become too American. She takes the time to not-so-subtly insult him at every turn. She tells them about a demon that has come in search of a glove--Lagos--and that she wants both Slayers at full strength to kill it. Buffy then goes to the mansion with Angel where they're practicing Tai Chi. One thing leads to another and they end up very close to a kiss. Buffy mentions Lagos, then leaves, knowing she can't let them get so close again.
At the library, Giles frantically searches for information on the demon, and takes out his frustration caused by Mrs. Post out on Xander and Willow. The two are both very tired but go back to researching. Willow has a headache and Xander rubs her temples to help her relax. They kiss and are almost caught by Giles, but stop before he sees anything. Feeling guilty, Xander offers to go check out the tomb where this demon would most likely go.
Walking on the streets, Buffy and Faith talk about guys and Faith tries to get info about Buffy's relationship with Angel, but Buffy is still too confused about it all and doesn't want to talk. Faith offers to take a final sweep through one of the cemeteries while Buffy claims to go home, tired. Faith runs into the demon and gets beaten up pretty badly, but she's okay since she's the Slayer. While looking through the cemetery, Xander sees Angel coming out of the mansion and going over to the garden (The mansion happens to be next to the cemetery.) After following, Xander finds Buffy and Angel in a passionate kiss which they later break and Buffy feels very bad about it. Angel shows her he has the glove that Lagos wants.
Giles and Mrs. Post continue their research at Giles' home. Just as Giles starts to pour some tea, Xander runs to Giles and tells him about what he saw. The next day at school, Buffy's friends hold a sort of intervention for her after finding out about Angel's return. Everyone expresses their feelings, while Buffy does her best to defend her case. After everyone leaves, Giles reminds her of the torture Angelus inflicted on him and harshly chides her for what he perceives to be a lack of respect for him. Post visits Faith at her rundown apartment and after a brief lecture carefully worded to distance her from the Scoobies, they train.
Buffy confronts Willow about her situation, but finds that she's not mad at all--which has a lot to do with Willow and her own secret. Later that night at the library, Giles calls Mrs. Post to come in and he tells her that a friend of Buffy's is holding it until they can get there and destroy it. He tells her where the mansion is and then when he's not looking, she hits him over the head with a statue, knocking him out. Buffy asks Willow to accompany her to a night of slaying since no one else could be reached. They talk and Willow is just about to tell Buffy about her relationship with Xander when Lagos shows up. Buffy fights him, and kills him with his own weapon.
Meanwhile, an angry Xander is playing pool at the Bronze when Faith shows up. He tells her about Angel's return and she decides that she should kill Angel before he has a chance to use the glove. They arrive at the library and get weapons, but just as they're leaving, Xander discovers Giles knocked out in his office. He calls 911 as Faith jumps to the conclusion that Angel did it. She leaves and he stays with Giles--he's not convinced that Angel had anything to do with it. At the mansion, Angel has performed the spell for the living flame needed to destroy the glove and Post arrives, claiming to be a friend of Giles' wanting to help with the spell. Angel goes to get the glove, and she hits him over the head with a shovel.
Buffy and Willow get back to the library to find the paramedics there, as they leave Giles tells her she has to destroy the glove with the living flame. Xander tells Buffy that Faith knows everything and she came to the conclusion that it was Angel that hurt Giles. Buffy rushes off to the mansion, asking Willow to find out how to destroy the glove. Back at the mansion, Angel gets up, revealing that he is a vampire, and fights with Mrs. Post. Angel easily defeats her. Faith arrives to see Angel beating on her Watcher and attacks him. Before Faith can stake Angel, Buffy stops her and tries to reason with her, to no avail. Listening to Post's suggestion that Buffy's feelings are clouding her judgement, Faith attacks her and a vicious fight erupts. Willow and Xander arrive, with Xander unsuccessfully trying to break up the fight between the Slayers while Willow attempts to help Gwen. But Gwen retrieves the glove, hits Willow with it, then puts the glove on.
Everyone stops fighting in time to realize that Post is wearing the glove. "Faith, a word of advice: you're an idiot!" she says to Faith. Finally revealing herself as the real villain of this story all along, she begins using the glove and the bolts of lightning that flow through it. She tries to kill Willow, who is pushed out of harm's way by Angel. At Buffy's suggestion, Faith distracts Mrs. Post, drawing her fire. Buffy then throws a large piece of broken glass and cuts off Gwen's arm, causing the now uncontrolled power of the glove to incinerate her.
At school the next day, Oz and Cordy are filled in on the details of the fight. Giles arrives and informs them that Post had been expelled from the Watchers' Council for abuses of dark power several years ago, but they had neglected to inform him. Everyone is cool with Buffy now, and they all trust her, except Cordelia. However, they all are still distrustful of Angel, for all of them are still scared by the recent memory of the soulless Angel's vile actions. Buffy goes to Faith at her motel room and tries to apologize and win back her trust, but Faith has given up on trusting anyone but herself.