Sci-fi RPG storyline

I'm working on a sci-fi RPG game that I will share with you people as soon as it is done. However, I ran out of creativity a few hours ago, and I need some help with a storyline. It has to be futuristic, and kind of... well, good

Preferably scary, and evil is even better. If you can give me some basic advice, I could turn it into something good. You just need to give me a start

Oh well, good luck, I guess
I **MIGHT** reward the "winner" with a new user title if I'm feeling really generous. We'll see though.