In the late 21st century, humankind came under a fierce attack from aliens who suddenly appeared via wormholes. They were helpless to fight against them and resigned themselves to imminent death. At that time, an ultimate weapon which could create items out of imagination was discovered in a expansive cave under Japan, along with its young master Ryuusei who was in cryostasis. The indiscriminate alien attacks awoke him and he led the humans to a decisive victory. The Defence Force of Earth decided to recruit girls with potential to fight. Even though they hesitated at first, they each had their own reasons to join. Thus, the special force ‘Blade Briders’ was formed, to protect the Earth against the aliens who have returned.