Wiktionary
end of story
alt. (context colloquial English) That is as much as I know, am prepared to reveal or am willing to say about the subject. n. (context colloquial English) That is as much as I know, am prepared to reveal or am willing to say about the subject.
Usage examples of "end of story".
It seems on the surface the simple answer would be that Thou Shalt Not Kill, end of story, but that's a little too easy, isn't it?