Continuity mistake: After Buffy decides not to take the antidote to the demon's venom, we cut to a scene at the mental institution. The doctor talks to her about ridding her mind of the things that support her "hallucinations". As he talks to her about this, the position of his hands change from pressed together in front of him to in his pockets between shots.
Continuity mistake: When the gang are fighting Glory's minions, one of them knocks Giles to the ground and then tries to choke him. As Giles hits the ground he lands facing downwards so we can't see his face. But when the minion is chocking him in the shot immediately afterward, he is suddenly facing upwards.
Continuity mistake: When Buffy is being offered the 'doublemeat medley' burger by her boss, the burger looks different in close up than in the long shots. In the close shot, the burger looks overall bigger, more filling is visible and there is more lettuce sticking out.
Continuity mistake: Just before Buffy storms out on Spike, she puts on her denim jacket. When viewed from in front we can see the jacket is only half over her shoulders and her hair is loose. The shot cuts to view her from behind, and the jacket is now completely on and her hair is tucked under the collar.
Continuity mistake: The first shot of Maggie Walsh being impaled from behind with the skewer indicates that there is no one standing close by, judging by the amount of negative space around her. However, following shots reveal that the skewer is coming straight out of Adam's wrist, therefore he should have been visible in the previous shot.
Continuity mistake: In 'Graduation Day, Part 1' when Giles stabs the Mayor, as he takes the foil out of his chest you can see a wound on his shirt. When the shot changes it has disappeared. I know the Mayor is invincible and his wound heal in seconds, but it still takes a second or two for his wounds to close up, they don't just disappear. (00:15:40)
Continuity mistake: The finger changes position in Buffy's hand as she picks it up. (00:23:35)
Welcome To The Hellmouth (1) - S1-E1
Continuity mistake: When Xander is talking to the girl at the Bronze his hand is on the pole and off the pole throughout.
The Harsh Light Of Day - S4-E3
Continuity mistake: Right before Spike jabs Buffy in the face on the college's campus, there are a ton of people around. But after he jabs her in the face and they start fighting, all of the people are gone.
I Only Have Eyes For You - S2-E19
Continuity mistake: When George shoots Mrs. Frank, her body falls off the balcony headfirst on a closeup shot. She flips in the air once on her way down. But in the following wide shot, she flips in the air on her way down again.
Storyteller - S7-E16
Continuity mistake: There is a shot where a girl is turning invisible, and when the camera switches to Buffy slapping her, she is fully visible, until it turns back and she is slowly becoming visible again.
Continuity mistake: After Doris from Social Services leaves Buffy's house and Spike leaves after her, he takes his lighter out of Buffy's pocket. But earlier in the episode when everyone was packing away all of Willow's magic stuff, Buffy finds Spike's lighter and puts it in one of the boxes.
Tabula Rasa - S6-E8
Continuity mistake: When the gang is in the Magic Box and they pass out, we see Buffy fall on the floor at the top of the stairs, but in the next shot she has moved and is now lying on the steps.
Continuity mistake: When you first see Adam lying on the bed, before he wakes up you see his human side of his face on his right side. In the next scene the camera is over Maggie Walsh's shoulder and the human side of his face is now on the left side. Then just after he stabs Maggie it switches back again.
Continuity mistake: The shape of the hole in the aluminium foil in the Winnebago's windshield changes shape several times throughout the course of the episode.
Continuity mistake: When Buffy, Dawn and Joyce say goodbye to Doctor Kriegel after being given Joyce's medication, the position of Dawn's hair changes between shots.
Some Assembly Required - S2-E2
Continuity mistake: When Cordelia is being tied up in the corridor, Buffy leaps up, kicks the attacker, and drops to the ground next to Cordelia. In the next shot the attacker is stumbling to his feet, and Buffy is standing again, then quickly kneels down beside Cordy.
Chosen answer: Angel is saying that he is still jealous and Buffy recognizes that this is his way of saying he wishes that they could be together. That is why they both smile.