“Elvis & Nixon” (** out of four) was an unconvincing biographical period melodrama about the untold true story of the meeting of President Richard Nixon (Kevin Spacey) and The King (Michael Shannon) and their opposing yet similar viewpoints on the world. Both Shannon and Spacey are terrific actors but both seem miscast. While some of the backstory of Elvis is interesting, the eventual meeting of the two at the end of the movie is heavy-handed and flat. For a more perceptive look at Nixon, watch Oliver Stone’s 1995 “Nixon”.