The Monks of St. Thomas Affair - S3-E5
Factual error: Illya leaps onto the rope in the monastery tower, causing the bell to ring. After sliding down the rope to the floor, he then identifies the tone as "B Major 7th." But the musically-literate Illya should know better. B Major 7th is a chord (B, D-sharp, F-sharp, A-sharp), not a single note. (00:41:45)