 In the far future, Earth is a polluted hell with massive cities and a crime problem to match. Keeping the peace is the Tank police that literally use tanks as both their vehciles and main weapons with a nearly insane brutal dedication to their job. Leona Ozaki, joins them as the first female member, and must find a way to work with the others in her own style. That s something that has to be settled soon considering that the notorious Cat Girls and their dumb male partner are planning crimes that require Leon s skill to stop.