Other mistake: When Angel fights with Buffy in the forest you can see that he hasn't got shoes on, just socks. Later, when Buffy goes back to the mansion and Angel is chained up, he's wearing shoes. How did he manage to put them on, if he was in chains?
Continuity mistake: When Buffy is in the counsellor's office she is wearing a yellow kind of gauzey cardigan which alternates between being completely buttoned up to unbuttoned between shots.
Revealing mistake: In the teaser of "Beauty And The Beasts", when Jeff is running through the woods, you can see in the top left corner of several shots a lamp being used to light the scene.
Homecoming - S3-E5
Continuity mistake: In numerous episodes, including 'Homecoming', we see vampires being killed when they weren't stabbed through the heart (the Texan girl vampire in this episode is stabbed practically in the stomach). But the show also makes an issue of the fact you have to stab a vampire directly in the heart to kill it (think the flashback in 'the Becoming, Part 2' where Buffy misses the vampire's heart, or 'Pangs' where Spike gets staked several times).
Homecoming - S3-E5
Visible crew/equipment: When Buffy and Faith are in the library, a person's arm wearing a white shirt can be seen on the left side of the screen behind Buffy in one shot.
Band Candy - S3-E6
Continuity mistake: The tattoo on Giles' arm is reversed compared to the way it was facing in the "Dark Age" in season 2.
Revelations - S3-E7
Revealing mistake: When Gwendolyn Post fights Angel in the mansion, she breaks a long-handled shovel over her knee to create a stake. If you watch in slow motion, the handle of the shovel is pre-broken (she simply holds the two pieces together tightly), and the pieces separate just before they actually make contact with her knee. (00:34:55)
Revelations - S3-E7
Revealing mistake: In 'Revelations' when Buffy and Faith are fighting, the kick Faith aims at Buffy's face right after she says 'We can work this out' very noticeably misses, but Buffy still reacts as though it landed. (00:36:15)
Revelations - S3-E7
Visible crew/equipment: In the Buffy/Faith fight right around when Buffy says "We can work this out..." You can see what appears to be a boom mike bob in and out of the frame in top left. (00:36:15)
Revelations - S3-E7
Deliberate mistake: In the fighting scene, the glove of Myhnegon is used by the new watcher who directs it toward the ceiling of Angel's living quarters where there is a huge skylight. The skylight is not seen in any other episode and its presence would have burned him on other occasions. (00:38:10)
Revelations - S3-E7
Continuity mistake: When the female watcher is being destroyed after Buffy cuts off her arm. Her sleeve is empty, which is not possible, as Buffy could not have removed the arm but not the sleeve. Also the arm on the floor is removed at the elbow, but the watcher has lost the entire arm in a previous shot.
Lover's Walk - S3-E8
Continuity mistake: In the episode Lover's Walk, when Spike is threatening Willow at the factory, in the long shots Willow's hair is up over her face, and in the close-ups it isn't. The pointed bit of the bottle is at the top or bottom in different shots too. (00:19:20)
Lover's Walk - S3-E8
Continuity mistake: In the scene where Xander and Willow are stuck in the factory Xander wakes up you'll notice that the blood on his side burn closest to his ear constantly changes lengths from shot to shot. It goes from under the chin to slightly below where the blood on the other side of his side burn is. (00:30:30)
Lover's Walk - S3-E8
Continuity mistake: In the scene when Spike was in Buffy's kitchen with Joyce, Buffy keeps him down on the table and grips Spike by the throat. She uses her left hand (in the close shot it is also the left hand) but in the next scene when Angel is also in the kitchen and Spike hits Buffy's hand, she uses her right hand (Spike hits her right hand).
Lover's Walk - S3-E8
Other mistake: In the final scene, where Spike drives down the road while singing 'My Way' he turns the steering wheel significantly, but in the external shots the car is travelling down a straight road, with no bends. He is turning it sharply to the right as the camera cuts to outside, but the car continues straight ahead.
Lover's Walk - S3-E8
Revealing mistake: Early on, Spike falls down drunk. He wakes up because his hand is on fire from the sunlight. When he runs away, a little bit of fire stays on the stones where his hand was when it started.
Continuity mistake: Near the start of 'The Wish', the scene where Cordelia is talking to the Cordettes and meets Anya. During the close-ups of Harmony, Anya is standing to camera right of the brunette Cordette behind her. A few seconds later when the shot is further away Anya is standing camera left of the Cordette. (00:05:40)
Visible crew/equipment: Just after Cordelia says "let's go to the Bronze", check the top of the screen - a microphone drops into shot for Harmony's line "is that a joke?" (00:16:20)
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.