The genuine scream in Roman Holiday
Audrey Hepburn will forever go down in Hollywood history as being one of the most charming and charismatic actors. While she was chock-full of talent, her infamous squeal in Roman Holiday is credited to Gregory Peck. He was a prankster that took his stunts to the limit, even on set.
While speaking about the Mouth of Truth, he explains that it bites the hands off of liars. The script told Gregory to pretend that it was chewing off his hand, but that wasn’t enough for him. After pulling his hand out of the statue, he presents to Audrey a stump, which catches her by surprise. Her horrified scream and laughter afterward were entirely genuine.