Operation Han-Gyaku-Sei Million Arthur Japanese: Hangyakusei Million Arthur The sacred sword "Excalibur". A sword that was created to judge a person's ability to be the king of England. Those whom the sword accepts will be called "Arthur" and will obtain great power. However, there was not a single Arthur but many. Due to this massive creation of legendary humans, the world and its history began to be distorted. Now, with the aim of restoring the history of the world to its original course, six Arthur, a master of the sword, a fighter, a sniper, a puncher, an alchemist and a shooter, set out for England. Their mission is to defeat all those who have managed to obtain a power from the sacred sword Excalibur and are using that power to distorting the world, which is around a million people.