In fact when you combine stem cell technology with the technology known as tissue engineering you can actually grow up entire organs, so as you suggest that sometime in the future you get in an auto accident and lose your kidney, we'd simply take a few skin cells and grow you up a new kidney. In fac
I think audiences will always like bad guys who kill for no apparent reason. We just like to hate them.
Usually, in the studio, on this sort of thing... you just go out and have a play over it, and see what comes, and it's usually - mostly - the first take that's the best one, and you find yourself repeating yourself thereafter.