An elite unit belonging to the Japan Block of Eagle, an international secret defense organization established by the United Nations to protect humanity. In the story, they are simply called "Goranger", and the name "Secret Squadron" is only used in the title of the work and the lyrics of the theme song.

The surviving members of each branch of Eagle's Japan Block, which was devastated by the attack of the Black Cross Army, received ranger training under the command of General Commander Edogawa Gonpachi and became the Gorenger, a special force that fights the Black Cross Army to protect peace on Earth. There are five regular members, but there are also reserve Gorenger members selected from within Eagle, such as Kumano Daigoro.