I can tell a similar story about being in a horror movie with a mate in my teenage years ... someone on here may be able to identify the film as I can't remember the name.
A disembodied hand was crawling across a floor towards a room where a man was sitting in the dark, so you can imagine the tension in the audience.
The hand knocks on the door and the man yells in a terrified voice: "Who's there?"
My mate shouted out "Andy" and the whole cinema erupted.
