In literature, deus ex machina (Latin for "God from the machine") was a plot contrivance that, while unrealistic, solved a seemingly unsolvable problem by adding something unexpected to it. Some people considered it "an outdated literary device."
The 2373 introduction of a benevolent Rukani vessel to the holonovel Insurrection Alpha by Kathryn Janeway was an example of this. Tuvok praised her addition, calling it "a very effective plot development." (VOY: "Worst Case Scenario")