Oops! What Should I Do If I Get Cheated by the Prince?

Is there really a way to come back from the dead in this world? I just lost my memory, The unique skills of medicine and poison that he possessed out of thin air made everything confusing. In order to let her sister escape, she became a substitute princess. But he entered a carefully designed situation. Everything points to the truth, she is not herself, Behind the truth, there is a bigger picture... Above the chess game, misplaced love and hate intertwine, Who is the final winner?