In the year 2045, after an economic disaster known as the Simultaneous Global Default which destroyed the value of all forms of paper and electronic currency, the "Big 4" nations of the world are engaged in a state of never-ending "Sustainable War" to keep the economy going. In this world, Mokoto, Batou and other members of Public Security Section 9 have contracted themselves out as mercenaries under the group "GHOST", using their cybernetic enhancements and battle experience to earn a living while defusing hot-spots across the globe. However, the emergence of "Post Humans" and a conspiracy uncovered by former Chief Aramaki force Section 9 to reunite.