Just an awful, awful idea from every angle, the initial plan for Dennis Hopper's character of Frank Booth in Blue Velvet was for him to be inhaling Helium for kicks rather than Amyl Nitrate. Thankfully, David Lynch had a full-time drug abuser on set with him, in Hopper himself, who suggested that someone of Booth's persuasion would opt for Amyl Nitrate instead. It was a wise choice because Hopper was able to craft with this one of the most terrifying psychopaths in cinema history. It's difficult to imagine the scenes playing out even remotely as effectively if Hopper was sporting a squeaky voice and still trying to sound menacing. Still, with the benefit of computers, we could always raise the pitch ourselves and give it a try...