In futuristic MegaTokyo, the reprieve from Boomer attacks has come to an end, and after a nearly two-decade vacation, the Knight Sabers have reappeared to protect the city, but with a fifth member, Priss' teenage daughter, Yumeko.
And now, after the events of Next Generation, Yumeko is living in Sacramento under a different name, the only way to stay safe from the long arm of Genom. The Knight Sabers are enjoying a brief vacation, but everyone knows that it's too good to last...
...especially with a woman named Katherine Madigan as the new Genom CEO.
Enter MegaTokyo and Sacramento in the year 2055.