What is an example of metaphor in the play, Fairview?

The "mirror" on the fourth wall of the Frasier family home, i.e. the invisible fourth wall between the audience and the action of the play, is a metaphorical representation of the different levels and layers of seeing and perception that manifest throughout the play. The Act One characters pretend that both the mirror and the wall are there, a common convention or way of staging a play that many audiences are familiar with, and accept. On another level, though, those characters are, in reality, looking into the audience when they are looking into the mirror. This idea seems to make the metaphorical suggestion that when they see "themselves" in the "mirror," they are actually seeing "themselves" in the eyes and perceptions of the audience. This idea is developed further in Act Two, when new characters, mostly non-black characters like the people who are probably in the audience, comment on what they see in the lives and actions of the black characters. The comments go even further in Act Three, when those non-black Act Two characters take on the roles of additional members of the Act One black family.