Old English plot "small piece of ground," of unknown origin. Sense of "ground plan," and thus "map, chart" is 1550s; that of "a secret, plan, scheme" is 1580s, probably by accidental similarity to complot, from Old French complot "combined plan," of unknown origin, perhaps a back-formation from compeloter "to roll into a ball," from pelote "ball." Meaning "set of events in a story" is from 1640s. Plot-line (n.) attested from 1957.
1580s, "to lay plans for" (usually with evil intent); 1590s in the literal sense of "to make a map or diagram," from plot (n.). Related: Plotted; plotter; plotting.
in fiction, the structure of interrelated actions, consciously selected and arranged by the author. Plot involves a considerably higher level of narrative organization than normally occurs in a story or fable. According to E.M. Forster in Aspects of the Novel (1927), a story is a "narrative of events arranged in their time-sequence," whereas a plot organizes the events according to a "sense of causality."