Directed by Venkat Prabhu, Massu is the story of Massu (Suriya) who plays a street smart guy finding unusual ways to con people with the help of his friends. One day he meets with an accident which changes his life and begins to witness unreal incidents taking place. This is the time when he meets Malini (Nayanathara) and falls in love with her. Due to the accident he starts seeing a number of dead souls which keep haunting him and ask for his help for personal gains. Out of the dead souls he also meets a spirit which looks exactly like him who haunts him in exchange of a favor. What happens after that forms the crux of this thriller.