In a world oppressed by the malevolent Vandel who controls creatures of darkness, a courageous group known as the Vandel Busters fight back. Among them, the Zenon Squad stands out as the mightiest on the land. Beet, a young aspirant, harbors the dream of joining this elite squad. However, a tragic misstep by Beet leads to the Zenon Squad's fall at the hands of the devil Beltose. In their final moments, the dying squad members transfer their life force into the Saiga, five powerful weapons entrusted to Beet before passing away. Now, bearing the weight of their legacy, Beet embarks on a quest to fulfill the Zenon Squad's mission and bring an end to the era of darkness.