I'm sure this happens all the time.. I came up with what I thought was an original idea, but somebody had beat me to it. Nothing is new under the sun, and all that jazz.
I'll probably never get around to writing it, but I had an idea for a novel that blended contemporary urban fantasy with sword and horse through the simple expedient of introducing something I've been calling "the Shadow". It came upon humanity as a surprise, and nobody (it seems) really know what caused it, why it happened, or how to reverse it.
The Shadow is some substance that had flooded the earth that caused a complete arrest of not only technology, radio waves, electricity, etc... but also combustion itself (happily taking guns out of the equation, as well). This is just a plot device, though. The world-building, the characters, and the messages would all be my own.
The problem is that the idea isn't so original. The show "Revolution" is using the same idea, but I've been told that an author named S.M. Sterling had published a novel using that very same idea in 2004. I haven't read it, and I don't want to for fear of it having an influence over me if and when I do decide to write this thing.
Which leads me to my question: If I did write a novel using this idea as a major plot device, and I put my own spin on things to make it a unique story, would I then be able to submit it to agents without those agents rejecting it outright because of a "stolen" idea? I've read enough Butcher to understand that borrowing ideas is part of the craft... *cough*Pokemon*cough*... but this seems to me to be more significant than that.
I don't know why I'm worrying about it. I'll probably never get around to it, and even if I do finish it, I don't really stand a chance at getting published. I have about /zero/ fiction writing experience. If I do this, it'll just be something that I do for myself (and maybe I can force it upon a few of my closer friends). I have free time, I'm leaning towards getting serious about time management and actually giving this a serious go..
Thoughts?