This is the only John Carter cover in which I intentionally deviated from the story. In the actual scene, the Master Mind does not appear, but Lester del Rey thought the cover painting should go along with the title, so I took the liberty of placing the character in the scene. The composition reflects my concern for uniting the front and back sides of the cover painting. The arch of the wall and the tubes and equipment in the foreground form an oval that both focuses attention on the center of action, the operating table, and involves the white ape in the scene.