Buffy and Angel leave the Sun Cinema after seeing a film called Le Banquet D'Amelia -- which turned out to be much steamier than they'd expected. To prove that he isn't going to lose control, Angel kisses her, but their sweet moment is cut short when Faith shows up for patrol. While out hunting for the bad guys, the two slayers run into a demon who offers to sell them the Books of Ascension for $5,000. Apparently, these books would be very useful against the Mayor, so when he finds out about the offer, he asks Faith to kill the demon and take the books.
At the library, the Scooby Gang discusses "Ascension," but they know very little about it until Willow suggests checking in a book which Giles keeps hidden from her due to its magical content. Inside is a reference to a diary entry which warns of an Ascension the next day and the entire town he inhabited disappeared overnight. Cordelia Chase arrives and makes a date with Wesley. Faith finds the demon, who's desperate to get out of Sunnydale before the Mayor's Ascension, and kills him. She goes to Angel, apparently upset over what she's become and seeking comfort from him. Angel refuses to comfort her the way she wants, but Faith manages to sneak in a kiss on the cheek which Buffy happens to see. Faith's attempt to seduce Angel having failed, the Mayor decides to take his soul in the most painful way possible.
Buffy reports to Giles and Wesley, but having just seen Faith with Angel, a little upset and reluctant to do anything with Faith. After Xander gets the address for the demon from Willy, Buffy goes to find him, and Faith arrives just in time to tag along. When the two reach the demon's apartment, they find him dead. The Mayor talks to a shrouded man about taking Angel's soul away from him. Buffy tells Willow about how she saw Faith and Angel together, and Willow encourages Buffy to talk to Angel about it.
Faith finds Angel first at the mansion and apologizes for her behavior the night before, and then she pours blood onto his shirt. The shrouded man steps out of the shadows and chants a spell. Lights flash, Angel yells, and Angelus is back. He pulls Faith to him and they kiss before Angel starts beating her up. The two fight and Faith ends up on top, holding a stake to his heart. A truce is made as Angel agrees to meet the Mayor and the two kiss.
The gang meets again, and makes plans for the night. Willow reveals that she was unable to find anything in the Mayor's computer files since the files were emptied before she could get through to them. Unable to find Faith and Angel, Buffy leaves to find out what's going on with the Mayor while Wesley takes a very eager Cordelia and the rest of the group, minus Xander, to the Hall of Records to find information on the Mayor. There, Willow finds a photograph of the Mayor which is over one hundred years old, confirming that he isn't human.
Faith takes Angel to meet with the Mayor, and Angel tries to kill him, but discovers that the Mayor can't be killed. He tells the Mayor of his plans to torture and kill Buffy. The two walk the streets of Sunnydale on the way to Buffy's house, and encounter Xander who Angel punches and knocks to the ground. After charming Joyce, Angel and Faith find Buffy in her room and lure her away to the mansion. Once there, Angel and Faith reveal that they're fighting for the other side now, and Angel knocks Buffy out cold.
Angel chains Buffy to a wall, where she wakes up finding Angel and Faith planning to torture her. Faith goes on about her painful childhood with a mother who drank too much, and her life as the Slayer living in Buffy's shadow. She reveals what she knows about the Mayor's master plans, which will culminate with the Ascension taking place on graduation day. Finally, Faith says with a smile, boasting her ability to deceive the Scoobies: "What can I say? I'm the world's best actor." Angel responds: "Second best." Faith then realizes that she has been the duped -- everything that has occurred throughout the episode has in fact been a ruse set up by Buffy and Angel to expose Faith, and Buffy slips out of her chains. The rest of the Scooby Gang arrive as Buffy and Faith fight and end up with knives at each other's throats. Before anyone is killed, Faith breaks away, kisses her on the forehead, and runs off, knowing that Buffy wasn't ready to kill her yet.
At the library, Giles says good-bye to the shrouded man, revealing that the mysterious figure had come to Giles at the beginning and put on a light show in order to pay back a debt the man owed Giles for introducing him to his wife. Wesley is very upset that Giles did all this behind his back, and plans to tell the Watchers Council about it; Giles surprises him by saying that he should, remarking that he can think of nothing more dangerous than a rogue Slayer. Now that everyone is fully aware of Faith's having switched sides, they have to prepare to fight her as well. Faith is upset over the whole ordeal, but the Mayor tells her not to worry because after the Ascension they'll all be dead.
Buffy goes to Angel, and both are having a hard time dealing with what they had to do. Angel feels horrible that he had to do and say the things he did, and how far he let it go. Buffy needs some time, but as she leaves, he asks, "You still my girl?" and she responds, "Always."
Faith's turn to the dark side becomes public knowledge by the end of this episode.
Wilkins shows again his strange father-daughter relationship with Faith when he asks Angel to bring her back before 11 o'clock. Faith reveals the deep resentment she has kept behind her happy-go-lucky face.
After meeting Skyler, Buffy allows him to depart unharmed rather than slaying him, noting that he seems harmless. This marks the widening of one of the Buffyverse's overall themes, that demons are capable of being benign whereas soulless vampires are not, a concept introduced in "Becoming, Part One" and explored more fully in the Angel spin-off.
The Scoobies discover the Mayor's immortality and that he is posing as his own grandson.
A sorcerer quite similar to the cloaked man in appearance and power appears in the Angel episodes "Awakening" (where he does in fact remove Angel's soul, as the cloaked man in "Enemies" only pretends to do) and "Calvary".
This episode marks the return of Cordelia as a regular member of the Scooby gang, she is taking part in research without any back story and will be a regular part of each adventure from now on.
The Mayor worries that killing Buffy would bring about another Slayer, not knowing that the Slayer line begins with Faith, and not Buffy.
Faith is freaked out about killing a demon and having its literal blood on her hands; this is the first of two incidents of this nature, the second is the Angel episode "Sanctuary"
Skyler, killed by Faith
Behind the Scenes
In the opening scene, Buffy and Angel have just seen Le Banquet d'Amelia, a fictitious movie.
Buffy says, "the girl (Faith) makes Godot look punctual," a reference to Samuel Beckett's existential play Waiting for Godot (in which the unidentified Godot never shows up).
Buffy and Willow had an exchange cut due to length:
Buffy: "I can't stop thinking about that demon."
Willow: "'Cause of him being chopped up into little bits and all?"
Buffy: "Yeah, Will, let's keep bringing on the visuals."
And Wesley is funny:
Wesley: "You failed in last night's mission because you lacked faith. If you had simply...'Lacked Faith'. A pun. From me! Well. Bet you never thought I had the funny in me, eh?"
French: Trahison (Treason)
German: Gefährliche Spiele (Dangerous Games)
Joss Whedon states in an interview on the Season 3 DVDs that fans had been eager to see Angelus again.
Faith - “Well, you see, when I was a kid, I used to beg my mom for a dog. Didn’t matter what kind. I just wanted, you know, something to love. A dog’s all I wanted. Well, that and toys. But mom was so busy, you know, enjoying the drinking and passing out parts of life, that I never really got what I wanted.”
Mayor Wilkins - "I've got two words that are gonna make all the pain go away: Miniature. Golf."
Wesley - "And you say this demon wanted cash? That's very unusual."
Giles - "Demons after money. What ever happened to the still-beating heart of a virgin? No one has any standards anymore."
Buffy - "It's down by the bus station. Not the nicest part of town."
Giles - "Again, see? No standards. Any self-respecting demon should be living in a pit of filth or a nice crypt."
Mayor Wilkins - "There's more than one way to skin a cat. And I happen to know that's factually true."
Xander - "What's this Ascension mean?"
Giles - "I'm not sure."
Wesley - "No, not really a common term in demonology."
Willow - "Ooh ooh! The Marenschadt Text. I think in the section on genocide, they mention Ascension."
Buffy - "Well, we have a winner."
Xander - "And, more importantly, two losers."
Giles - "Where did you find that volume?"
Willow - "In the top of your book cabinet with the stuff you try to keep hidden."
Xander - "Hidden? Are there any engravings I should know about? Uh, frolicking nymphs of some kind?"