According to "Phrase Finder" website, the phrase "deus ex machina" is derived from Greek dramas, meaning "something or someone that comes in the nick of time to solve a difficulty, especially in works of fiction." 

Reality show contestants battle for a slot on next week’s episode and will do whatever it takes to win.  All but one contestant who refuses to compete.  The show itself is unraveling as the crew plots mutiny, contestants display ever-increasing disturbing behavior, and disease threatens to call everything to a halt.  Who will come to save the day - deus ex machina?