Evil King and His Doctor Princess

In this medical family she was the genius who was well informed about pharmacology and medical skills. Once, she accidentally travelled back to the ancient times and her soul lived in the body of the daughter of the prime minister. She heard that her new identity was used to be a useless person, and even was foolish? Now, this body belongs to a new strong soul, she must change her life! He is said to be an extremely ugly prince and was poisoned before his 25th. What story will be staged when these two people meet?