In a routine patrol at the cemetery, Buffy fights with a vampire. Buffy has the upper hand, but when she attempts her killing blow, the vampire turns her stake around on her, and she is stabbed in the abdomen. She attempts to flee, but is cornered, and the vampire, wielding her stake, is about to finish her off, but Riley appears at that moment and fights him off before going to see to Buffy.
The next morning, Riley patches up Buffy's stab wound; the embarrassing circumstance of nearly being killed by a lesser vamp with her own stake is not lost on her, and leads Buffy to fear that she may be losing her edge despite Riley's reassurance. While Riley suggests she go to the hospital, Buffy feels it would only upset her mother, and her enhanced healing abilities will kick in soon enough. Dawn comes in to tell them Joyce is coming up, prompting Riley and Buffy to hide the gauze and medical supplies they were using. Joyce notices a bottle of rubbing alcohol and asks if they are disinfecting something, prompting Dawn to say it was hers. Buffy asks Riley to take the rest of the gang to sweep the cemetery that night.
Meanwhile, Buffy, wanting to learn and avoid future mistakes, does research with Giles to find out how previous Slayers died, but they are unable to find any useful information, mostly because past Watchers either found the subject too painful or were killed along with their Slayers. Buffy remembers that Spike killed two, and confronts him in his crypt. Later, at The Bronze, she lays down ground rules: if he tells her what she wants to know, Spike gets a wad of money. Though initially resistant to giving her anything useful, Spike barters with her for a plate of spicy Buffalo wings, as he refuses to talk on an empty stomach. In doing so, Buffy inadvertently reveals her stab wound, leading Spike to annoy her further. Asked if he's always been this annoying, Spike says "I've always been bad."
London, 1880 - That assertion is belied, however, by the quiet, shy, rather foppish gentleman William used to be -- a young man who feels disconnected from others in British society. While at a society ball, he works on a love poem, looking for another word for "gleaming" ("a perfectly perfect word as many words go, but the bother is nothing rhymes, you see"), but his unfinished work is snatched from his hands and read out loud, to the rude amusement of the boorish crowd. William is dubbed "William the Bloody" because of his "bloody awful poetry". One listener declares that he would rather have a railroad spike through his head than hear more of William's poetry.
The poem reveals his feelings of love and adoration for a woman. He speaks with the object of his affection, Cecily, whom he has loved from afar. She does not care for him and, when he admits the poem is about her, she rejects him, telling him that she feels nothing for him, and that he is 'beneath' her. William, devastated, leaves the house in tears, bumping into a group of strangers (Angelus, Darla, and Drusilla) in the street. In a hay barn, he sits ripping up his love poems, when Drusilla appears before him. She asks what brought him to tears and comforts him by telling him that she sees his greatness and worth. She promises him a better future by her side, siring him after only minimal persuasion.
Back in the present, Riley and the gang find several vampires loudly and drunkenly reveling in a crypt, including the one who staked Buffy. They decide to return in the morning when all the vampires are asleep, rather than take on the entire nest awake. Spike plays pool while continuing his tale. After his siring, Spike was completely different. Tired of being left out by the world, he became empowered and destructive.
Yorkshire, 1880 - Angelus throttles William at the bottom of a coal mine, asking why they haven't killed him yet. William, now having adopted his distinctive accent and swagger, notes that he goes by the name 'Spike' now. Spike's strong tendency to incite mob riots simply for the joy of the fray is causing trouble for his new vampire family; his most recent hijinks resulted in their having to hide in an abandoned mineshaft. Angelus feels that Spike's uncouth behavior is putting them increasingly in danger from being hunted by angry mobs. Spike feels Angelus only engages in fights that he knows he will win, rather than fighting with zeal and veracity. Angelus prefers the artistry of killing, seeing it as separating them from being mere animals. Spike's insults finally cause Angelus to lash out viciously, and he very nearly stakes Spike before Spike notes that he has proved his point. The elder vampire notes that if he cannot teach Spike the error of his ways, someday an angry mob would; that, or the Slayer. Spike sits up, suddenly interested, and asks, "What's a Slayer?"
Spike explains to Buffy that thereafter, he became obsessed with finding and defeating the Slayer of that era. He notes, as the first lesson, that a Slayer must always reach for her weapon, but a vampire already has all the weapons he needs (he vamps out to demonstrate this). To illustrate this point further, he tells her of the first Slayer he killed.
China during the Boxer Rebellion, 1900 - Spike fights with the Chinese Slayer, and after a long battle, he kills her when she reaches for her stake that she had dropped during the fight. While Spike and Drusilla revel in the kill of the Slayer and the taste of her blood (which Spike declares to be a powerful aphrodisiac), Angelus seems distracted and suggests they leave soon, as the rebellion is boring him (only later, in the subsequent, corresponding episode of Angel, will we learn the real reason for his distraction: the recent return of his soul, a secret he had kept from all except Darla). Spike proudly claims that it was the best night of his life, "and I've had some sweet ones."
Buffy is disgusted at how he got off on it, but he counters that even if Buffy kills tens of thousands of vampires in her lifetime, all it takes to kill a Slayer is for one vampire to have "one good day", and that Buffy simply got complacent at the moment of truth. Meanwhile, Riley returns to the vampire nest alone, despite agreeing to wait. After staking the vampire that hurt Buffy, Riley blows up the rest of the vampires in the crypt with a grenade.
New York, 1977 - Spike tells Buffy how he killed the second Slayer (Nikki Wood). Spike and Buffy fight out a play-by-play of the battle, which took place on a subway train. Spike notes that this second Slayer was not all business like the first - she had an improvisational style more closely resembling Buffy's. After he snapped the Slayer's neck, he took her black leather coat for himself. Spike then explains that the key to his victories was not in the particular moves or blows; the key was that each Slayer has a death wish, a desire to experience death, after causing so much of it, additionally claiming that Buffy also has this wish, but has "ties to the world" that keep her anchored. They want to know what comes next, because they wish for a final peace after a lifetime of being solely responsible for protecting the world from demons. Spike explains that the second that that desire takes over, the Slayer will die, because there are countless vampires just waiting to take advantage of this, a conclusion that Buffy immediately rejects.
Spike and Buffy are standing almost nose to nose by this point, and Buffy quickly becomes shocked and confused when Spike comes on to her, trying to kiss her before grabbing her by the arms and challenging her to prove him wrong, claiming that he knows she wants to "dance". In response, a contemptuous Buffy pushes Spike to the ground and, echoing Cecily, says, "It wouldn't be you, Spike. It would never be you. You're beneath me." With this, Buffy throws the money at Spike and proceeds to simply walk off into the night.
Crying softly, Spike begins to gather up the scattered bills, but his feelings of sadness and humiliation are quickly overtaken by anger and hatred. Furious, Spike returns to his crypt and arms himself with a double-barreled shotgun, intent on killing Buffy for her final insult. Harmony begs him to reconsider his plan, because he has tried and failed so many times before. She reminds him that the chip in his head will not let him hurt a human, and the Slayer will only beat him up again, if not stake him outright. Spike retorts that his pain will last for a couple of hours, and Buffy will be dead much longer than that.
South America, 1998 - Drusilla turns away from Spike's devoted love because she cannot look at him without seeing and feeling the Slayer, after Spike and Buffy's original alliance against Angelus. In the background is a Chaos Demon, with huge slimy antlers, with whom Drusilla had been shamelessly flirting. She recognizes, long before Spike does, his feelings for Buffy, and rejects him because he is no longer the same creature that had satisfied her for so many years. He insists that he did it all for her, to protect her, because he loved her, but she cannot be convinced.
Buffy returns home, still shaken from the combined experiences of the last 24 hours, and finds her mother packing clothes and toiletries into a suitcase. She inquires where Joyce was going, and her mother explains that her health condition has worsened to the point that she is going to stay in the hospital for observation and a CAT scan. This final revelation is too much for Buffy, who retreats to her back porch in tears. At that moment, Spike approaches with his shotgun, full of resolve born of rejection and anger. However, he slows his pace when he sees that she is crying. Her pain stays his hand, his demeanor softens, and all his plans to shoot her are abandoned. He asks her what is wrong, and how he can help. She is surprised and confused at his reaction, and has no response, so he sets the gun down and takes a seat next to her on the porch. Spike, somewhat puzzled at his own behavior, hesitantly lays his hand on Buffy's back and gently comforts her, an action that Buffy does not rebuff.