Trivia: In the movie, Buffalo Bill cocks his revolver and inadvertently warns Clarice he is about to fire. The book explains this was a part of his ritual to terrorize his victims before killing them. He would follow them in the dark basement until his got bored and then cock his gun so they'd know they were about to die. He expected Clarice to react the same, but she instinctively shot him before he realised what was happening. (01:49:00)