Opera House Murder Case: File 2 - S1-E22
Other mistake: At the beginning of the episode, the characters are gathered thinking back about part 1 of the case. Amazingly enough, the propmaster's armpit ate the A of his shirt. Now he's not a "BADMAN", he's a "BADMN." (00:02:05)
Opera House Murder Case: File 2 - S1-E22
Continuity mistake: There's a blatant coloring error regarding Kindaichi's clothes when he speaks to the inn's manager through the window; his shirt goes from orange to lilac, with a pea green undershirt. (00:09:05)
Opera House Murder Case: File 2 - S1-E22
Other mistake: When Okata discovers the clue about the first murder in the recording room, the shadow cast in close-up is different from the wider angle - and it's also an impossible one, because the only light in the room is the one of her own flashlight, which couldn't be angled at the trolley that way. (00:11:25)
Opera House Murder Case: File 2 - S1-E22
Other mistake: In the flashback with the sulphuric acid bottle dropping on Fuyuko, the bottle has still the cap on, making the incident as it is shown impossible. It should also be noted that there's a shattered glass noise, but in the previous episode we saw the bottle was perfectly intact on the floor and was even reused for a murder (although how could the culprit be in possession of it is a mystery - it's the same one since the stain on the label is identical). (00:15:55)
Opera House Murder Case: File 2 - S1-E22
Character mistake: Like the previous episode, Fuyuko Tsukishima's name is transliterated wrongly in "Tukishima" on the cover of the diary.