In ancient Greek and Roman theater, the term originally referred to a literal device used in stage productions to lower actors onto the stage, often representing a divine or other supernatural figure who intervened in the play's events. This theatrical technique was used to resolve complex plots and conflicts in a way that seemed miraculous or beyond human control.
In modern storytelling and literary analysis, the term "deus ex machina" is used more broadly to describe any sudden and unexpected resolution to a complex situation or problem without sufficient logical or narrative buildup. It is considered a weak or unsatisfying plot device because it bypasses the natural development and progression of the story and can disrupt the reader's sense of immersion and credibility.
Critics often dismiss deus ex machina resolutions as cheap or lazy storytelling, especially when the introduced element or character lacks proper foreshadowing or integration into the plot. However, when used skillfully and in moderation, deus ex machina moments can surprise readers and create dramatic impact, especially in genres such as fantasy or comedy where the unexpected can be more readily accepted.