The plot revolves around the activities of the secretive Division 731 of the Ministry of Intelligence (MOI) who were tasked with among other things ending the war as quickly as possible. To help achieve that aim the members of Division 731 construct a secret base at Phoran on Virgon. There the members of Division 731 conduct cruel medical experiments on prisoners handed to them by the Colonial Government to improve the combat efficiency of the Colonial Forces. Their work is put under threat however by an inspection being carried out by an aide of the President who wants to know just what exactly is happening at Phoran to the prisoners sent there.