A new type of Boomer with advanced AI is stolen. It's up to the newly re-formed Knight Sabers to get it back. They will have their hands full with a group of Combat Boomers headed by a criminal scientist.
After taking time off, The Knight Sabers are back in action, thanks to a string of robberies performed by an evil organization called the Illegal Army, who takes up arms and destroys the peace in MegaTokyo.
Boomers all over MegaTokyo are rioting and throw the city into chaos. In order to stop this disaster, the Knight Sabers must locate the mastermind behind it all.