Character mistake: Giles picks up the potential slayer Chao-Ahn from Shanghai in Episode 7.12, "Potential". However, when she arrives in Sunnydale (Episode 7.14, "First Date"), the language she speaks is neither Mandarin nor Shanghainese (the two main languages spoken in Shanghai), but Cantonese, which is not widely spoken there. (00:08:55)
Continuity mistake: In many historical flashbacks, most notably Spike's and Anya's, hair and wigs differ greatly from previous flashbacks or episodes. The director even discusses it during the commentary on Lies My Parents Told Me, saying that he doesn't understand why the wigs aren't consistent.
Visible crew/equipment: When Dawn and the other girl are getting up after falling through the bathroom floor into the basement, you can see a man standing behind them towards the left side of the screen.
Visible crew/equipment: When Xander is in the bathroom after Buffy called him to look for the talisman, he bends down and grabs the talisman that lays under the sinks. As he stands the camera pans up to the mirrors and on the left side you can see the reflection of a crew member crouching over the hole to the old school. It's not the female manifest spirit as the clothes are wrong and she then appears from a different part of the room.
Character mistake: When Buffy is looking around the new high school, encountering the first sign of the school being haunted, there is a notice board in one of the corridors entitled "theatre". This is the British spelling. Sunnydale is in America and therefore the word should be spelled "theater".
Beneath You - S7-E2
Revealing mistake: When Buffy throws Spike into the benches at the church you'll notice that as he is about to hit the floor there is a blue mat where he lands. (00:36:15)
Beneath You - S7-E2
Continuity mistake: Shortly after the opening credits we see Buffy, Dawn and Xander driving to the new high school. As they're talking, the rest of the credits roll by onscreen. Just after "Producer: Marc David Alpert" is shown, there is a side-angle shot of the car and you can see Xander's left arm resting outside on the open door window. But in the following shot he has both his hands on the steering wheel.
Continuity mistake: In episode 'Same Place, Same Time', Gnarl cuts Dawn across the stomach paralysing her and ripping her shirt, but when Buffy and Xander are carying her home there is no tear in her shirt or any blood. Also when Buffy goes back to kill Gnarl he tears her shirt but seconds later the rip has gone.
Continuity mistake: In the final scene with Buffy and Willow at the end of the episode, the position of Buffy's right bra strap keeps changing throughout the entire scene.
Visible crew/equipment: After Gnarl poisons Dawn and traps Willow inside his cave, the shadow of a camera is visible on some bushes on the left side of the screen as we see Xander and Buffy carrying Dawn home.
Other mistake: We're shown a variety of photographs and pictures of different members of the gang at one point. One of those, the one of Xander and Anya, is actually a shot from the episode "Something Blue". I doubt very much that during the events in that episode, someone conveniently decided to take a photograph.
Visible crew/equipment: When a guy asks Dawn out to Winter Formal and she says "What?" - you can see a microphone at the top of the screen. (00:33:35)
Continuity mistake: When Cassie and Dawn were talking, just before Cassie got kidnapped, Cassie put her hand on Dawn's shoulder, but in the next shot, her hands were by her side.
Continuity mistake: Towards the end, when Buffy stops the arrow, when she first grabs it her hand drops down to Cassie's mouth level, and her arm's bent at the elbow. When we cut to another angle it's now held at arm's length and at about eye level.
Revealing mistake: When Anya sings her song about how she will become Mrs. Harris, she spins Xander's chair around after putting a blanket on him. When she is also sitting on the chair, and you see an overhead shot of them both, you can see a section of the stage floor rotating beneath them keeping the chair spinning.
Continuity mistake: In the flashback to St. Petersburg, 1905, just after the burning man runs out of the room, Halfrek mentions the Revolution. Between shots, Anya's champagne glass switches from her left hand to on the table and back.
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.