It's a world of rust and runes; metal and magic.
 
She's a gunmaker with a metaphorical heart of gold.
 
He's a bounty-hunter with a literal heart of stone.
 
She's wounded. He's out of fuel. They're trapped on an isolate ranch, and the griefers are coming.
 
Only he has the tactical genius to get them out alive.
 
And only she can make the weapon for the job.
 
It's a battle for the ages.
 
But 8 years later, an even greater battle looms. 
 
This time, she has a family to protect.
 
And he's somehow ended up on the wrong side of the fight.