Absolute power corrupts in all ages and all administrations. This is a never-ending truth. The iron fist of graft in the velvet glove of government-run enterprise continues to expand the power of money-mad politicians and bureaucrats who abuse their authority, deceive the citizens, and line their pockets with financial kickbacks. The newly established Government Crime Investigation Agency (GCIA) vows to prosecute political corruption and uproot the evil that police and the courts have failed to find. The man given the ultimate authority to lead a cavalry against political corruption is government crime investigation agent Zaizen Joutarou!

Kazuto Marugoshi is a Tokyo Metropolitan Police officer who doesn't like using guns. Together with his colleague Teizo Isoji he saves damsels in distress and solves crimes both big and small on the mean streets of Tokyo while using only martial arts.