I can only remember one scene of a (possibly thriller) movie that I would like to watch again. The scene could be described as:
A man looks out of his apartment window and sees another man at a street corner, just in front of the building. He is standing, looking right at the window. He is not young and wears black clothes with a black hat. The man in the street was obviously waiting for the resident to watch through the window before killing himself
with a gun which he fired on his head(edit).
It wasn't the first apparition of this man in the street. He has been tracking him on a long period and at different places. Every time the victim met the killer, he was frightened because he thought this person would kill him, even if he would not. The goal of the "killer" (who finally killed himself) was to make its "victim" become crazy.