Han Yi Han was a outstanding surgeon. He specialized in two departments: general surgery and cardiothoracic surgery after graduating from the top medical school in South Korea. One procedure altered his entire existence. The patient died despite Han Yi Han's belief that he performed a successful operation. Consequently, his medical license was revoked. Four years later, Han Yi Han practices law as a medical litigation specialist. In addition, he attempts to discover the truth behind the death of his former patient. Han Yi Han protects victims and attempts to punish those who commit medical malpractice and neglect in his court cases. He works with a prosecutor who has lost a family member and a lover as a result of Han Yi Han's surgery.