The crossword solution for the term STORYLINE SHAPE is ARC, which is a three-letter word. An ARC is a curved line that forms a part of the circumference of a circle or other shape. It is also used to describe a continuous, smooth curve that connects two or more points. In terms of storytelling, an ARC is the shape of the plot, which is the sequence of events that make up the story. It is often used to describe the development of a character's journey throughout the story.