Cesar is a wretched man who subsists on the pain of others. Though the residents rarely take notice of him, Cesar furtively observes of every intimate detail of their lives, seething at the first signs of optimism and cheerfulness. Carefree tenant Clara is far too perky for Cesar; the happier she gets, the deeper her doorman sinks into despair. In order to be happy, Cesar realizes, Clara will have to suffer. Though at first Cesar's plan to torment Clara from afar goes off without a hitch, things start to fall apart when the scheming doorman gets too confident for his own good. Just as Clara begins to suspect that her curious bad luck streak may be coming to an end, however, Cesar summons all of his strength and resentment to deliver one last devastating blow.