The Bye Bye Man

In 1969, a mass murder occurs in which a man kills people on his block. As he shoots the neighbors, he continuously asks if anyone spoke about "the name" which cannot be said. He also repeats the same thing over and over: "Don't say it, don't think it; don't think it, don't say it." In present day, Elliot, his girlfriend Sasha, and best friend John move into an off-campus house not far from their college. Soon, mysterious things start to happen, such as Sasha developing a strange cough and Elliot finding coins in a nightstand that continually reappear. Elliot also finds writing consisting of "don't think it, don't say it", and a name: the Bye Bye Man. During a seance involving their friend Kim, the name is mentioned. Read more on Wikipedia.