The History of Metroid
In the year 2000 of the history of the cosmos, representatives from the hundreds of inhabited planets formed the Galactic Federation, and engineered a period of prosperity for the people of their planets. But as trade between planets increased, space pirate activity increased.
As a measure to keep the peace, the Galactic Federation organized the Federation Police Force and charged them with defending merchant ships from pirate raids. When the FPF became overworked and overstressed, the Federation sent out calls for brave sentients to track down and bring the pirates to justice. These bounty hunters became legendary figures, people to be admired, respected, and feared.
In the year 20X5 of the history of the cosmos, a research team returned from an expedition to an uninhabited planet designated SR-388 with heavy casualties and a very valuable prize: a life form they called "Metroid." Its species was apparently responsible for wiping out the civilization that once flourished on SR-388's surface. They brought it to their deep-space research vessel in suspended animation and studied it, finding that exposure to beta radiation would cause it to awaken and begin to multiply. Carefully locking it down, they prepared to return to Earth with their findings. En route, space pirates attacked the ship, killing the crew and taking their supplies, including the dormant Metroid.