The film is an ode to the voice of Indian cinema, Amitabh Bachchan. Shamitabh is the combination of ‘Sha’nawaz ( Dhanush), a mute passionate young man, who wants to be an actor and ‘Amitabh’ Sinha( Amitabh Bachchan), a wasted alcoholic rejected as an aspiring actor, years ago, for his deep non-conformist voice. Technology brings a speechless face and a faceless voice together to create a star called Shamitabh. All is good till Shamitabh becomes a superstar. The Clash of egos between the voice and the face, threatens to destroy it all. Till destiny decides their future.