“Deus Ex Machina: (Lat, “god from the machine) A theatrical device used in Greek tragedy. In several plays of Euripides, a god appears at the last moment to provide the solution to the tangled problems of the main characters. The god is let down from the sky on a sort of crane. The phrase has come to refer to a playwright’s use of external means to solve the problems of his characters—a practice generally frowned upon.”
Excerpted from: Murphy, Bruce, ed. Benet’s Reader’s Encyclopedia, Fourth Edition. New York: Harper Collins, 1996.