Xander and Anya watch a movie with Buffy and Riley while listening to the background noise of Xander's drunken parents fighting and yelling upstairs. The next day, the gang looks at a potential new apartment for Xander. He doesn't think he can afford it and this upsets Anya. Giles receives a visit from a demon searching for the Slayer. He later identifies the demon as Toth, only survivor of the Tothric Clan.
The Scoobies check out the city dump in search of the demon and find Spike collecting. The demon hits Xander with light from a rod and knocks him to the ground. He gets to his feet and walks off with the rest of the gang, but there is another Xander still lying in a pile of trash. The next morning, one Xander awakens at the city dump and then discovers his double upon returning to his house. Meanwhile, Spike has put together a Buffy doll from mannequin parts which he uses to practice beating up on.
One of the Xanders is very ambitious and gets a promotion at work, signs a lease for the apartment, and sets up a date with Anya. The other, unconfident Xander watches as all this happens and finally confronts his double. After the two Xanders see each other, the confident Xander talks to Buffy and she makes this a matter of Slayer business.
Soaked by the rain, weak Xander goes to Willow and tries to explain that this double is taking over his life. He tells Willow that the double is doing a better job of living his life but then suddenly realizes that his double is going after Anya and that is one thing he won't allow.
Anya and the Xander double discuss their future and Anya expresses her fears about not living forever. Giles discovers that the rod Toth used split Xander into two real Xanders, one with weak qualities and the other with strong qualities. The weak Xander crashes the date between strong Xander and Anya. Both think that the other is a demon and the weak Xander pulls out a handgun he got from Anya's apartment.
Buffy tells the doubles the truth about their situation and tries to convince them not to kill each other. Toth appears at the apartment then Buffy and Riley fight and kill him. They eventually begin to get along, and their actions become so similar to each other that the comment is made that Xander is a "bad influence" on himself. Giles and Willow research and come up with a way to reunite the two Xanders but Anya expresses disappointment over this as she wants both to stick around for some sexual shenanigans, much to the disturbance of the others. Willow ends the spell (literally -- she simply says "let the spell be ended") on the Xanders and makes them one again. While moving Xander into his new apartment, Xander and Riley talk. Riley confesses that despite how much he loves Buffy, he realizes that she doesn't feel the same.