the main character is freaked out for some reason and he's in a toilet in a restaurant or bar or something and some guy in a cubicle starts asking him to pass him some toilet paper.
He gets more freaked out and runs off, whilst the bloke in the cubicle is left with his hand sticking out from under the door.
It's a thriller I think. Perhaps. I can't remember what it is. Someone has to tell me.
It's not even that obscure, I just can't remember.