The Story at Its Heart:
She is the last surviving descendant of the former dynasty; he is the crown prince of the current one.
He thinks she is a spy. She thinks he slaughtered her entire family.
Their meeting begins with deception, and their hearts are trapped in a web of schemes.
He personally has her child taken from her; she watches helplessly as he marries another woman and makes her empress.
Only when he discovers that she was the one who saved his life as a boy does he realize the truth. But by then, she has already drunk the poisoned wine he gave her, and died with a smile.