Reika and other AG units arrived in orbit on Mars. An expedition by Reika, Arhena, Air, and Ryo was formed to explore the ancient Nibiru ruins left in the Valles Marineris. There, Reika and his friends are told by Air about the mysteries of ancient ruins left around the globe and the past of Nergal and Nibiru. Arhena listens to the content and remembers a passage from the Gilgamesh epic. A descendant of the Sumerians, she feels a fateful connection with Air.
Die Ancient Girls müssen auf der Reise zum Jupiter auf dem Mars haltmachen, um den Antrieb der Atra-Hasis reparieren zu können. In den alten Relikten der Nibiru finden sie allerdings mehr als sie erwartet haben.