Dr. Kenzou Tenma was an esteemed neurosurgeon who recently got engaged to his hospital director's daughter. However, his rise in the hospital hierarchy came to a halt when he received a call from the director during surgery, asking him to switch patients and perform life-saving brain surgery on a famous entertainer instead of the scheduled patient. Despite applause from his colleagues, fiancée, and the director, Dr. Tenma felt guilty about causing the death of an immigrant worker due to the switch. When a similar situation occurred, he stood firm and chose to operate on Johan Liebert instead of the town mayor. This decision led to serious consequences for him, including losing his social standing. However, after the mysterious deaths of the director and two other doctors, Dr. Tenma's position was restored. Nine years later, when he saved a criminal's life, his past came back to haunt him as he faced the monster he had operated on. To make amends for the harm caused, Dr. Tenma embarked on a quest of pursuit.