Buffy has to leave Dawn at dinner time to go out patrolling. At the cemetery, Buffy begins fighting a sword wielding demon. The demon disappears causing Buffy to believe that he's run away, but he's actually been absorbed into his sword which Buffy now claims as her own.
Dawn arrives at the Magic Box and asks if Willow, Xander and Anya would like to go with her to buy birthday presents for Buffy's upcoming birthday. However, they're all too busy to go with her and Dawn is left to go shopping on her own. Unfortunately, she does more stealing than shopping. The next day at school, Dawn is called to the guidance counselor's office and Dawn confides in her that she feels abandoned. She says that people have a tendency to go away and wishes that she could make them stop going away. That evening everyone arrives at the Summers house for Buffy's birthday party, including Buffy's co-worker Sophie, Xander's workmate Richard (who Xander and Anya wish to set Buffy up with) and Spike's floppy skinned demon friend, Clem. Tara also arrives for the party and although she and Willow try their best to talk to each other, they both find it quite awkward. Buffy receives her birthday presents, which include a hand made weapon chest from Xander and Anya and a stolen leather jacket from Dawn. Everyone seems to enjoy the party, especially Dawn who is clearly very happy about spending time with the people she cares about. The birthday party turns into a slumber party and all the guests decide to stay the night.
The next morning, everyone still feels like they don't want to leave. They soon realize that there is something or someone keeping them in the house and when they try to leave, find that they physically can't. Everyone talks about how they have things that they need to do and places they need to go, which upsets Dawn. She takes it personally, believing that they don't want to spend time with her and runs off to her bedroom. The gang follows her and asks if she has any idea why they are trapped. It seems like a huge coincidence that she doesn't want them to leave and now they can't. Dawn says that she knows nothing and then screams at them to get out of her room. Tara says that she could perform a spell to reverse whatever is keeping them in the house, but she has no magic ingredients with her. Willow then reluctantly admits that she hasn't got rid of all of her magic supplies after all. Tara performs a spell to free them from the house, but it doesn't work. Instead, it releases the demon from the sword. The demon stabs Richard with his sword and then disappears into the walls of the house.
Evening comes and everyone is still trapped. The demon can be heard moving around in the walls causing a very eerie atmosphere in the house. Richard is in need of urgent medical attention, Anya is feeling claustrophobic and everyone is feeling very much on edge. They all know that they must find a way out of the house soon. Desperate to get out of the house, Anya demands that Willow should perform a spell to try and free them, claiming that since she is a more powerful witch than Tara, it might work. Xander agrees that Willow should attempt to free them but Tara defends Willow and tells Anya to back off. Anya is now convinced that Dawn is responsible for them being trapped and decides to search Dawn's room for clues. Instead, she finds a lot of Dawn's stolen items – many from the Magic Box. Buffy talks to Dawn who admits how lonely she's been feeling. She also tells Buffy about how she accidentally made a wish to her guidance counselor. After Anya confronts Dawn about the stolen items, Buffy tells her about the wish Dawn made and Anya realizes that her vengeance demon friend Halfrek is responsible for them being trapped.
Anya then summons Halfrek. As soon as Halfrek arrives, the demon comes out of the wall and stabs her right through her chest. Buffy then manages to get the sword off the demon and once she has trapped the demon in the sword, she breaks it so that he cannot escape. Halfrek is fine, but refuses to reverse the spell and tells everyone off for ignoring Dawn. Although she refused to reverse the spell, Halfrek then finds that she too cannot leave the house, forcing her to free them all. The party finally ends and everyone is relieved to finally get outside. Buffy, however, chooses to stay in the house with Dawn.