1943, the height of World War II. A girl officer Maud Garret with a secret cargo gets into an American B-17 bomber "Flying Fortress" and immediately becomes an object of ridicule. The captain orders her to take a seat in the gunner's cockpit under the belly of the plane, from where the girl spots a Japanese fighter jet and a strange creature on the fuselage. She decides to tolerate sexist comments from the crew for the time being, but she does not intend to let enemy planes and sky goblins rule the sky.