An analysis of two plays by twin brothers, Anthony Shaffer's Sleuth and Peter Shaffer's The Royal Hunt of the Sun, reveals that the protagonists in the plays manifest the personality characteristics and interactions of twins even though they are not represented as such. Among these traits are mutual identification, role reversal, intense rivalry and affection, as well as a desire to keep things 'even'. Authors of novels and plays often express many of their own characteristics, tensions, and conflicts in their creations.