Bikel and Walter have a third brother: Brian, a peacekeeping robot commissioned by the FBI. However, when Brian returns for yearly maintenance, Dr. Asahina, creator of the Winspector Support Droids discovers that he has been heavily upgraded with high performance weapons and near invulnerable armor. In their attempts to create the ultimate law enforcement robot, the upgrades by the Americans also expose Brian's greatest flaw. Now it's a race against time to stop Brian, but nothing Winspector has can even scratch him. Only a new, untested prototype weapon stands a chance, but will it be ready in time? Can Ryoma even use such a dangerous device?