Counterplot and Underplot

noun

• A plot intended to subvert another plot.
  • synonyms: counterplan

verb

• Make a plot in response to another plot. .

• (n.) A plot or artifice opposed to another.
• (v.t.) To oppose, as another plot, by plotting; to attempt to frustrate, as a stratagem, by stratagem.

• (n.) A clandestine scheme; a trick.
• (n.) A series of events in a play, proceeding collaterally with the main story, and subservient to it.