It is the year 1999. The Machine Empire of Baranoia, led by Emperor Bacchus Wrath, has invaded Earth with the intention of wiping out all human life and bringing about machine rule. Chief Counselor Miura of the UAOH (United Airforce Overtech Hardware), in a desperate attempt to quell this invasion, has revived super energies born of the lost civilization of Pangaea. Enlisting an elite squad of the finest officers the UAOH has to offer, Miura has harnessed Tetrahedron Power, granting the team the power to transform into the Ohrangers… and save humanity from its darkest crisis yet!

In 2071, roughly fifty years after an accident with a hyperspace gateway made the Earth almost uninhabitable, humanity has colonized most of the rocky planets and moons of the Solar System. Amid a rising crime rate, the Inter Solar System Police (ISSP) set up a legalized contract system, in which registered bounty hunters, also referred to as "Cowboys", chase criminals and bring them in alive in return for a reward.