Deus Ex Machina

Deus ex Machina is a contrivance used in literary and film pieces as a unforseen twist in the plot line to often solve a problem that has been introduced. Deus ex Machina normally comes in the form of a character, device or event.

The Latin phrase "Deus ex machina" originates in the conventions of Greek tragedy. It refers to situations in which a mechane (crane) was used to lower actors playing a god or gods onto the stage. Though the phrase is accurately translated as "God from a machine," in literary criticism, it is often translated to "God on a machine." The machine referred to in the phrase is the crane employed in the task. 

Now that you know, look for the Deus ex Machina plot in the next movie you watch or book you read.