Possible Clues:

• Divine intervention in a play
• Unexpected problem solver
• An unlikely solution, requiring you to write in Latin?
• Pathetic person on street with one thing to keep off the rain
• Late delivery due different relations, parent and friend
• Unexpected aid
• Artificial plot device
• Friend, after exam, used to go bonkers -- a theatrical ploy
• Contrived agent who unexpectedly solves the insoluble
• Device in movies whereby a sudden intervention resolves a plotline