Visible crew/equipment: While Buffy, Giles, and the gang are in the library fighting the demon that came out of the Hellmouth, the camera zooms toward the door that leads into the hall, where you can see Xander being chased by the dead guys. As the camera zooms in closer towards the round window in the door, you can see its reflection in the glass when the strobe light flashes. (00:36:10)
Buffy The Vampire Slayer (1997)
2 visible crew/equipment mistakes in The Zeppo - chronological order
Continuity mistake: After Buffy finds Morgan's brain, Willow pulls up Morgan's school file on one of the library computers without even touching the keyboard. One moment the monitor is on the desktop, the next it's showing Morgan's file.
Spike: You listen to me. [Kneels in front of her.] I've been alive a bit longer than you, and dead a lot longer than that. I've seen things you couldn't imagine, and done things I prefer you didn't. I don't exactly have a reputation for being a thinker. I follow my blood, which doesn't exactly rush in the direction of my brain. So I make a lot of mistakes, a lot of wrong bloody calls. A hundred plus years, and there's only one thing I've ever been sure of: you. [Buffy looks away; he reaches toward her face.] Hey, look at me. I'm not asking you for anything. When I say, "I love you, " it's not because I want you or because I can't have you. It has nothing to do with me. I love what you are, what you do, how you try. I've seen your kindness and your strength. I've seen the best and the worst of you. And I understand with perfect clarity exactly what you are. You're a hell of a woman. You're the one, Buffy.
Buffy: [Quietly.] I don't wanna be the one.
Once More, With Feeling - S6-E7
Trivia: In 'Once More, With Feeling' the man singing the mustard song is David Fury, the co-executive producer.
Question: Specific answer needed, not a general "dialogue is sometimes re-recorded". Near the start of this episode, Buffy's talking to Giles about the significance of the earthquake. Buffy's dialogue sounds completely normal and recorded at the time, but all of Giles' dialogue is dubbed. I can only think he had a sore throat that day or similar, but does anyone know the specific reason he did his later?
Chosen answer: He had larangitis and because of the shooting specifications they had to have him shoot the scene with a bad throat, they then re-recorded his lines and dubbed them. At various points during the scene and indeed the episode you can see him touch his throat or rub it.