Anne: Buffy's hiding in Los Angeles after killing Angel at the end of Season 2. While her friends attempt to battle vampires back in Sunnydale without her, she has to face up to who she is when she finds a demon abducting homeless children and working them to death.
Dead Man's Party: Buffy has a party at her house to try to reacquaint herself with all her friends. Unfortunately, the party is crashed by a load of zombies. Fortunately, Buffy combines killing the zombies with making friends with all the Scooby gang again.
Faith, Hope and Trick: A vampire called Mr. Trick arrives in town, along with a new Slayer called Faith, who has replaced Kendra. Buffy accepts a date with a normal boy called Scott, while unbeknownest to her, Angel has returned from hell.
Beauty and the Beasts: Buffy finds out that Angel has returned but keeps it secret from the others. Asking Giles how, if, in a hypothetical situation, Angel came back, he would behave, Giles tells her that Angel would most likely be a crazed animal. Angel seems to live up to this at first, but by episode's end, he has become slightly vocal and placid again.
Homecoming: Buffy and Cordelia compete to be Homecoming Queen, Xander and Willow secretly kiss and Scott breaks up with Buffy. Angel and Giles are hardly present at all, but Buffy tells Angel that she won't tell the others that he is back.
Band Candy: Mr. Trick hires Ethan Rayne to produce some chocolate bars that make all the adults of Sunnydale behave just like teenagers. This is only a distraction, however, as the real target are babies from the hospital, who the Mayor of Sunnydale (obviously up to something not entirely very good) offers to tribute to a demon.
Revelations: A rogue Watcher comes to town to find a glove which gives her ultimate power. In the attempts to stop her, it comes to light that Buffy has been harbouring Angel, and her friends are consequently not very pleased with her.
Lovers Walk: Spike returns, convinced that Drusilla only broke up with him because of Buffy. He kidnaps Willow and Xander, to force Willow to do a spell to make Drusilla love him again. When Oz and Cordelia burst in to rescue them, they find Willow and Xander kissing. Upset and confused, they leave. Meanwhile, Buffy decides that she must stop seeing Angel.
The Wish: Cordelia, convinced that all her troubles are Buffy's fault, wishes that Buffy had never come to Sunnydale. Unfortunately, her wish is granted, and Sunnydale without Buffy turns out to be a dark and evil place. But hey, I love the vampire Willow! Just when I thought that girl couldn't get sexier ...
Amends: Angel starts having flashbacks of all the people he's killed, all of whom are urging him to kill Buffy. Needless to say, he doesn't. Most of the episode doesn't make sense anyway. The best bit, which isn't saying very much (and don't think this bit is good, it's just better than the rest of it) is the scene where Willow tries to seduce Oz because she feels so guilty about having been caught kissing Xander. (To be fair, this episode gets better on subsequent viewings, but it still doesn't make sense.)
Gingerbread: When Buffy's mum, Joyce, finds some children murdered by witches, Sunnydale experiences a violent backlash against Wiccan groups. Obviously, this is very bad news for Willow and Amy (of Season 1's 'The Witch'), who wind up nearly being burnt at the stake.
Helpless: The Watchers' Council set Buffy a test to make sure she is worthy of being the Slayer by taking away her powers and leaving her to fight a vampire who was a homicidal nutcase even when he was a human. Needless to say, she passes, but the Watchers' Council fire Giles for not being an impartial Watcher.
The Zeppo: Xander realises he isn't remotely cool, so he gets himself involved with a gang. Unfortunately, the gang turn out to be a gang of dead people, and they want to make Xander into a similar condition. After this experience, and getting himself out of it, Xander realises he's happy to be who he is.
Bad Girls: Faith tempts Buffy into living on the wild side for a while - but the time they spend together culminates in an innocent person dying as a result of overzealous Slaying. At episodes' end, Faith reveals that she doesn't care. Meanwhile, the Mayor of Sunnydale performs a ritual that makes him invincible, in preparation for his Ascension.
Consequences: Faith is kidnapped by the Watchers' Council so she can stand trial for killing the innocent person in last episode. Unfortunately, she escapes, but it isn't made clear at the end whether she's still loose or whether Buffy and company manage to recapture her.
Doppelgangland: The creators of Buffy realise just how sexy the vampire Willow from 'The Wish' was, so they bring her back. It's a pretty ludicrous premise, even for Buffy, but it's an incredibly fun episode where vampire Willow rampages around Sunnydale causing havoc.
Enemies: Faith tries to make Angel lose his soul so that he will attack Buffy and work for the Mayor. The Scooby gang finds out that the Mayor is over a hundred years old and built Sunnydale himself so that he can feed off its psychic energy. The Mayor will, apparently, 'ascend' on Graduation Day, which sounds rather bad.
Earshot: Buffy gains telepathic powers after a demon's blood touches her skin, but this isn't actually very good, because the ensuing cacophony of thoughts threaten to send her insane.
Choices: Buffy gets accepted to Sunnydale University, as does Willow, who also gets accepted to other places which are slightly better, like Yale, Harvard and Oxford, Britain (where she can "study and eat scones"). However, being really REALLY stupid, she decides to go to Sunnydale University anyway.
The Prom: Angel decides, with a little help from Buffy's mum, that him and Buffy staying together is a bad idea. After the Mayor ascends, he will leave for LA. Meanwhile, three Hell Hounds are bent on disrupting the prom, but Buffy, after having her heart broken by Angel's decision, is in no mood for such shenanigans, and kills the Hounds easily.
Graduation Day, Part 1 (Part 1 of 2): Angel is poisoned by an arrow shot by Faith, and Willow finds out that the only way to save him is to let him drink a Slayer's blood. Buffy goes out to catch Faith so he can do just that. Although Buff wins the fight, Faith deliberately falls off a high building to stop Buffy saving Angel.
Graduation Day, Part 2 (Part 2 of 2): Buffy goes back to Angel and lets him drink her blood instead of Faith's. Angel does so, then takes Buffy to hospital so she can have a blood transfusion. While there, he finds that Faith is in a coma, but still alive. At the graduation ceremony, the Mayor turns into a giant serpent and eats Principal Snyder. Loads of vampires start running around, but Buffy and the Scooby gang are ready for them, and they kill them all. Then Buffy blows up Sunnydale High to kill the Mayor, and Angel goes away to star in his own series.