The first sentence of this example is quite a mess despite not having any actual grammar or punctuation errors. (If it’s a foreign planet, the foreign country part is understood, isn’t it?) The second sentence is mostly okay. The third sentence is also awkward without breaking any rules of grammar, punctuation, etc.
Here’s the improved version:
You work on a foreign planet to free the innocent from prison. You find an old woman who says she is innocent but doesn’t want to be freed. You ask her why, then bend down to hear her whisper her reason.