A plot

noun

noun

The primary plot of a piece of literature, television, etc., contrasted with the secondary B plot.

The primary function of the A plot is to initiate the first movement and complication in the B plot and eventually absorb the B plot once it is resolved.1966, Blaze Odell Bonazza, Shakespeare's Early Comedies: A Structural Analysis:
Shows have an A plot and a subsidiary, or B plot...2001, Robert Keith Sawyer, Creating Conversations: Improvisation in Everyday Discourse:

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