Man from Another Place: Where we're from, the birds sing a pretty song... and there's always music in the air.
When Leland Palmer is locked in the cell he starts screaming and runs headlong into one wall, then the other. The first wall wobbles noticeably on impact, indicating it is being shot on a set.
Laura Palmer's murder was supposed to remain unsolved, but ABC demanded that the murderer be revealed. Many people believed that that moment was when the series jumped the shark.