Smile Time - S5-E14
Continuity mistake: Angel is coming down the hall in the Smile Time set and he sees the trash man walking past him. In the behind shot, Angel is farther back, but when it shows the side and front shot, he's right behind him.
Audio problem: During Lilah's failed attempt to rescue Angelus, when Gunn shoots at Angelus with the tranquilizer gun, Angelus passes out then hits the ground. When he is about to pass out, we hear the sound effect of him hitting the ground before he even begins to fall over, and instantly in the next camera angle he hits the ground. (00:08:20)
Continuity mistake: When Wesley tells Faith that Angelus is back, she says, "Step away from the glass" and hangs up the phone. When Wesley jumps from his chair (to allow Faith to smash through the glass and escape) you can see Faith behind the glass with her hands up to her face and standing, but in the close up of Faith her hands are at her sides and she is only just getting out of her chair. (00:23:20)
Continuity mistake: When Fred is running from the oncoming white car, she runs toward a blue car getting fixed on the side of the road, but jumps out of the way as the white car hits the blue car. Fred hits the ground and rolls over to the fence, but in a following shot it shows Fred only just hitting the ground and she is on the grass, not next to the fence. (00:14:20)
Continuity mistake: When Jasmine picks up the car and throws it at Angel, it cuts to a shot of Angel moving out of the way then shows the car falling from the bridge. First mistake, Jasmine disappears from the shot when the car is falling, and second, the car falls directly straight and at a higher point than Jasmine actually threw it. (00:35:50)
Blood Money - S2-E12
Continuity mistake: During the charity event when it shows the birth year and death year of Holland Manners, it suggests he was 49 years old when he died. But in an earlier episode, he attempted to sacrifice his daughter for his 50th birthday.
Revealing mistake: When Cordelia goes to see Lilah, the eyelashes of her real eye can be seen blinking Underneath her "black" eye after she sits down.
Other mistake: The Chinese writing shown tattooed all over Wo-Pang's body is nonsense (a small number of random characters repeatedly jumbled together), although Wesley reads it as if it is language. (Although one might argue that the writing is meant to be some sort of code, there is no evidence in the show itself to suggest that, and Wesley refers to "translating" rather than "decoding" it; for these reasons it is more likely to be simply a mistake rather than an intentional decision.) (00:16:40)
Revealing mistake: At the vampires' nest, when Knox is talking about Gunn's team, the vampire wearing the green sweatshirt and leather vest doesn't have yellow eyes like the other vampires do. And the female vampire doesn't either later, when the two groups face off after Gunn's sister is sired. (00:22:30 - 00:35:35)
Continuity mistake: When Angel and the others infect Connor with Cordy's blood, Gunn rips open Connor's shirt. In the following shots, the shirt closes and then opens again. (00:41:40)
Disharmony - S2-E17
Continuity mistake: When Angel pulls Cordelia aside and says that Harmony cannot work with them, a man in the background walks past in the shot of Cordelia but we never see him walk past in the shot of Angel.
Smile Time - S5-E14
Character mistake: While Gunn and Lorne are interrogating Framkin he sings a couple bars of a song "Courage and Pluck". However, though he has the ability to read people when they sing, and in fact in the very next episode knows that Fred is about to fall from just the words "you make me happy", Lorne doesn't read him.
Continuity mistake: When the demon Angel and Groo are chasing crashes through a wall, the resulting hole lets in enough sunlight to force Angel into the shadows. A few shots later, Wesley notices Angel standing in the entrance to the hole. Only a few moments have passed, so Angel shouldn't be able to stand where he is. (00:15:20 - 00:16:20)
Other mistake: Later in the day when Cordy has recovered a little and is cleaning, Angel says something about seeing a reflection in the picture. We hear Cordy say, "What do you want," but the subtitles say, "What do you what?"
Answer: Everybody including Angel saw her. After helping them and then being left alone to talk to Angel, Cordelia says that the Powers That Be let her come back one more time to help them. After Angel gets a call saying that she died, he realises that it was her spirit that was helping them the entire time.