A nightmare is outside the door

Overview

Jung-in is the professor of western psychology decides to take a break of his teaching and moves to his new house in country side with his wife. They went to say hello to their neighbor and when there was nobody at home, they left a note. Next day the neighbor comes to visit at 4pm. When he left the couple didn't think it was a simple response to the note they left. But the doctor, neighbor comes everyday and ruins the couples peaceful times. As time passes, the couple. the couple feels pressure and drives them insane.