Hmm....what about a apocalyptic world that was destroyed in world war three. The radiation from the bombs killed everything, and the humans survive by fighting back the BioMass- a kind of mutation that occurred from the radiation. I picture a Captain soldier kind of person who is out on the search for survivors in the Ruins of the world. The Captain could be a girl or whatever, and she has her team with her- and she comes across a couple of survivors in the basement of a obliterated house maybe? A guy maybe who is opposed to the Military.
Okay, I'll be honest. That came off the top of my head!