So thanks to Lirliel I came up with this idea. We've decided we're not going to us it but I would still like to explore it with some one. It is as follows;
The One God rules supreme. By Divine Right, three Mortals rule each World. But only two of them are known to the populace - the third is only known to the Slaves who labor deep underground. They rule the 'Underworld', as it is called, the Army, and the People. All share their power though the Ruler of the Underworld is kept hidden from view.
Slaves from off world have long been brought to the planet, mining the crystals that power all forms of machinery and electricity. But one amongst them will rise up, to lead them to freedom, to overthrow the ruler of the Underworld and his two above-ground counterparts. He would topple the regime and free the Planet from its evil rule. Who will come to his aid?
The young wife of the ruler of the Underworld - married through a forced marriage that brought her family great power and standing - has often visited the Underworld, the realm where her husband rules with an iron first. One man amongst the many has caught her eye, and she see's something in him that she has not seen in any man before. She is drawn to him, breaking all rules and morals of some one of her stature. For she has started to fall in love with this man.
Rumor spreads like wildfire, of unrest amongst the Slaves. The King of the Underworld tightens his grip, but only she - his wife - can see who will rise up from amongst the Slaves to take his place. She comes to his aid, realizing that what is set in motion will reach beyond this world and possible cripple an empire.
I am looking for this wife - "Queen" of the Underworld.
Technology is powered by these crystals, and travel between planets is possible (though not fully understood) while weaponry is still rather archaic, though Warhammer-ish. Violent hand held weapons though no guns.