The Holy Knights are supposed to have exterminated the "Seven Deadly Sins," a gang of evil knights who plotted to conquer the realm of Britannia, however some claim they still exist. After ten years, the Holy Knights launched a coup and assassinated the king, establishing themselves as the kingdom's new dictatorial rulers. Elizabeth, the king's only daughter, embarks on a quest to locate the "Seven Deadly Sins" and seek their assistance in reclaiming the realm.