In the year 21XX, Sigma's rebellion had finally been crushed, and all Mavericks were neutralized thanks to the efforts of a Reploid scientist named Dr. Doppler. Using his advanced Neuro Computer, Doppler was able to create a "vaccine" to suppress any abnormal behavior in the Reploids and prevent them from going berserk. This brought about an era of peace. Many advanced Reploids and reformed Mavericks gathered near their new mentor and founded "Dopple Town" in his honor, a perfect utopian community. With Dr. Doppler guiding them, the world seemed ready to enter a new golden age...