The Diagram is a secret organisation founded and led by King Taravangian of Kharbranth, dedicated to executing a master plan to save as much of humanity as possible from the coming Desolation - by any means necessary. The plan itself is also called the Diagram: a vast, sprawling set of predictions, instructions, and calculations that Taravangian produced during a single day of supernatural intelligence granted by the Nightwatcher, one of Roshar's Old Magic entities. The Diagram's agents operate across Roshar, manipulating politics, assassinating rulers, and making alliances that serve the plan's cold calculus of acceptable losses.