The film is set in a small town, where nothing ever happens, apparently, because the tiny town holds secrets. There, in a completely ordinary house, lives a very shy boy who does not stop hearing a knock inside the walls of his house. The little boy begins to suspect that something strange is happening in his house with his parents and when his new teacher arrives, she will tell him about his suspicions. The new guardian will begin to wonder what happened to the little one’s first teacher.