"For the ancient Greeks, the god of theatre was Dionysus—the 'god of the mask.'  Initiation into the mysteries of Dionysus was a passage through ecstatic possession and transformation into the mysteries of identity—appearance and reality, death and rebirth.  This god with many faces was also the 'god of confrontation' whose entranced eyes 'cannot be avoided'" (Mask Improvisation for Actor Training & Performance: The Compelling Image, 1996).  Illustration from Plays For Players And Guide To Play Production by Verne E. Powers, 1957.