Alternate Dimension

So talking over my book with my wife, I realized how far I deviated from my original novel idea. 
I don't want to get rid of what I've written, but I also want to tell that original story.  I can't do it as a sequel or prequel.
The way it is now, it is a complete science fiction story.
Originally it was a supernatural horror story.
The only writer I know who was able to combine the two was H.P. Lovecraft.  Read during his own time he wrote supernatural horror.  Read now, it is science horror.

I think what I may have to do is write two different novels, with the same characters, same locations, possible same conclusion, but drastically different in theme and style.

Stephen King did something like this with Desperation (I loved it), and then released a Bachman book called the Regulators (not as good in my opinion).  Both had the same characters, involved similar locations, but were very different from each other.
Other times movies have done this.  Anyone who is a fan of Donny Darko knows that there is an American version and a directors cut.  In the American version, it seems more like God is calling to Donny using an avatar named Frank.  In the directors cut, they are advanced beings from the future.

I don't want to cheat the story, that is my primary concern.  Am I being lazy by not wanting to rewrite the entire story?
Such a conundrum.