In the XXIV century, mankind is pretty much known as the "Federation of Earth", and has gone to deep space to colonize other planets.
But around the year 2350 a mysterious virus spreads around the colony planet of Velia, but targeting only the female population-- women are then morphed into brutal killing-machines, enslaving males in the process.
The female Velians then evolve into a very aggressive hive mind-like society, and turn on the Federation.
The game itself begins seven years after the beginning of the war between both factions, when the player's character, Senior Sgt. Paul Armstrong of the "Federation of Earth", finds himself forced to single-handedly take on the Velians when they attack his ship.
Operation: Matriarchy, as released, contained no in-game music, but in August 2007, a fan-made mod was released, adding a complete score and enhanced sound effects to the game. Also, the story was rewritten.
Later, in September 2009, a second fan-made mod was release - this one offered a complete (yet completely optional) translation to German and even further changes to the in-game sound effects and music. However, this mod is mostly known for the introduction of massive changes to the visuals, adding enhanced lighting and improved versions of many textures and bump maps.