在这部千铳士动画片中,古枪vs现代枪，绝望之战——
全世界因核战争而荒废，在那之后的时代——。在世界帝府的绝对统治之下，人们全都受到管制，在被夺走了自由的世界中生存。
但，在一切武力均被禁止之时，还存在着为了打破世界帝的独裁而暗中持续抗战的反抗运动。他们手持作为美术品留下的“古枪”，发起挑战。以及，如同呼应其灵魂般现身的古枪化身“贵铳士”。高贵华丽地战斗的他们所拥有的“绝对高贵”，给世界带来一线希望——！
获得生命，生机勃勃地闪耀光辉的年轻贵铳士们的日常。欢笑、哭泣、喜悦、迷茫、时而受伤，即使如此也一心追求自身的“绝对高贵”而战的美丽年轻人们的故事。我们为何而战，又应守护何物——
Be Noble！
Despair War is a battle between ancient guns and contemporary guns. Due to a nuclear war, the world was destroyed. Under the full governance of a world empire, people are living with their freedom taken. Despite the forbidden rule of owning any weapons, there is a resistance that secretly fights against the world empire. They own ancient guns left as art and fight using these. Then, the Kijuushi appear as the souls of the ancient guns. Proud and magnificent, the "Absolute Royal" are the only ones that can give hope to this world. The story depicts the everyday life of the Kijuushi. Laughter, despair, happiness, confusion, pain; they would still pursue their own absolute loyalty to fight.
