Marked-off pieces of ground, and the shapes stories take. Both are areas someone drew a line around.
Old English plot (a small patch of ground), of obscure further origin; the narrative sense arose in the 16th century, perhaps crossed with French complot (a conspiracy) — both a marked-off patch of earth and a marked-off shape of story.
Marked-off pieces of ground, and the shapes a story takes — both simply areas someone has drawn a line around.