When the Wischtech threatened to invade the fiefs of Szaalanden, the Emperor dispatched fourteen youths. Of these, the Seven Heroes halted the invasion to herald a time of prosperity while the four Lances of Betrayal were supposedly defeated.

Two decades later, the Lances of Betrayal have reappeared and formed a bandit militia near the frontier fief Gormbark. A man with a black sword and a scar over his left eye slays an entire troop of that militia. He is identified as the boy, Kóinzell, and becomes as much an object of fear as of hope even as his own past, motivations, and purpose are a mystery to those he meets on his journey.

From Volume 0's back cover (SBM's translation):
"When the black sword roars, everything that stands before it is crushed . . . ! What is the purpose of a boy Kaintzel who possesses transcendent sword skills? The battle with the "Lances of Betrayal" that were supposed defeated by the 7 Heroes... And the astounding truth that is revealed after the battle."

Volume 0 encompasses a plot arc which leads directly into the main plot of Übel Blatt in Volume 1. It also introduces and develops the attitudes and motives of a few other characters aside from Kóinzell.