By the mid 21st century the world has been devastated by environmental pollution and world war. Failed attempts to repair the environmental damage have made travel by air and sea impossible. With 35% of land now underwater isolated cities rely on mercenary corporations for protection from terrorism and crime. Arqon Global Security is a private military corporation that provides protection for Fort Daiva City. They use transforming motorbikes called Maneuver-Blades piloted by Blademen. The Blademan receives technical support from an operator who works in a central command center. Karaya Sakurako works for Arqon Global Security as an operator with Blademan Saiki Cryde as part of an elite unit known as Viper. They are fighting against a terrorist group known as Hound which is using unmanned weapons called Bugmecha which were left behind after the war.