In a futuristic world where the internet and cybernetics has blurred the borders between societies; the members of Public Security Section 9 are reinstated to assist in solving numerous cases of cyber crime. A spate of similar crimes committed by separate suicidal groups known as "The Individual Eleven" becomes the core focus for Section 9 as war approaches in the form of refugees flooding into the country.

Crest of the Stars and Banner of the Stars (series I and II) follow Jinto Lynn, a young count whose world is taken over by the space-dwelling race of the Abh. When Jinto was a young boy, his father, Rock Lynn, under threat of invasion, handed over their world, Martine, to the Abh in exchange for a position within Abh society.

In the year 2029, the barriers of our world have been broken down by the net and by cybernetics, but this brings new vulnerability to humans in the form of brain-hacking. When a highly-wanted hacker known as 'The Puppetmaster' begins involving them in politics, Section 9, a group of cybernetically enhanced cops, are called in to investigate and stop the Puppetmaster.

In the future, life between the digital and physical world has been blurred. The boundary of technology and humanity has been stretched beyond imagination with lives being led in both the electronic and physical worlds.

Three years after their adventure, Lafiel becomes captain on the brand new assault ship Basroil and Jinto finishes his training to become a supply officer and joins Lafiels crew. They set out to join a large fleet with the mission of defending the strategically important Laptic Gate from a force 15 times larger than their own.