Ideals for future project

I'm sitting down right now just resting up for my next class and I had some ideals pop into my head. I had a little back story I came up with but i'm working on the details now. All I can say now is that it's about a underground society and how a team of four Agents went rogue after they found out what the society is really about. That's all I have right now, hopefully I can come up with some more ideals to make this story really good and very deep.