It is 2300 AD. 192 years after the world has united, "ORS" (Orbital Ring System) was built 300 km above the Earth. ORS functioned as the center of industries, and provide energy to the Earth. One day, unknown outer animals (or human beings?) attached and occupied ORS. Their next target was the Earth. To protect the Earth, the United Earth formed a special unit, called "Space Nights". During this battle, Space Nights saved one mysterious boy’s life. His name is D Boy who can transform into "Tekkaman Blade". He fought against the enemies for the Earth, and beat them one after another. But there is a strong enemy standing in front of him. This enemy looks just like Tekkaman Blade. What is a secret of D Boy? Why only he can transform into Tekkaman Blade? What is the enemies purpose of invading the Earth?