Here's the sentence: "What I can tell you is that, hidden within the question, lies the answer." It makes sense, but I don't really know it's it right.
I figured that the "hidden within the question, lies the answer" part is an inversion of "the answer lies hidden within the question," but in the original sentence, there is a comma after "question," while if that part were to stand alone, it wouldn't need the comma (I think it might even be incorrect to include it). So does that mean the original sentence doesn't need it either?
As for the comma after "that," something similar applies, but it gets even more confusing. If the sentence were "What I can tell you is that the answer lies hidden within the question," it wouldn't need any commas. Does the original sentence need a comma after "that" because "hidden within the question, lies the answer" is an inversion? Or could "hidden within the question" be a parenthetical and therefore the reason it is between the two commas? In which case, does the sentence have to make sense without the parenthetical? Also, does "lies the answer" on its own even make sense? Does "lies the answer"?
Hopefully you can help me find the answer!