The female lead is also a female assassin who infiltrates a political marriage to become one of the prince's prospective wives in order to kill the prince.
The main lead had an accident and he is forced to quit working at a hospital after being accused of medical malpractice. He starts working in a prison with the goal of acquiring enough connections to take his revenge.
Genre of story quite similiar: Historical, forbiden love of noble figure, political, intrigue , tragic.