They provide their own theatrical reality, conventions one accepts and believes in.
But as can happen with environmental or site-specific events - as such productions are sometimes called - bright ideas resulted in disappointingly dim theatrical realities.
'The Capeman' lives in a musical reality for Paul, and I don't think he knows what he wants in a theatrical reality," said Mr. Simonson.
"I have worked so hard to establish a theatrical reality," said Glenn Wein, co-creator of "Grandma Sylvia's Funeral," in which the audience joins the mourners.
But there can be different kinds of theatrical realities.
"It's a more present-tense form than theatrical reality," she said.
For some reason, seeing theatrical reality turned on its ear in this giddy fashion is a kind of liberation.
In these plays, Meyerhold tried to return acting to the traditions of Commedia dell'arte, rethinking them for the contemporary theatrical reality.
Through his use of lighting and props as well as focus, Mr. Levinthal gives a flesh of theatrical reality to the fantasies involved in playing with dolls or toy soldiers.
That shouldn't be surprising, however, given the deepest impulse behind solo performance, which is to create a theatrical reality all by oneself.