Season 1

Dr. Kenzo Tenma, a leading neurosurgeon at the Dusseldorf Hospital has received massive acclaim for his successful surgery on a famous opera singer. However, he is burdened by guilt. Due to pressure from the director, he had operated on the opera singer on the night that he was supposed to operate on another man. As a result, when the director’s orders him to operate on the mayor, he decides to ignore the order and instead works on saving the life of a young boy, brought to the hospital from the scene of a serial homicide. However, the boy's twin sister, who was brought in with the boy, and who still suffers from shock, keeps repeating the words 'kill him'.

The price for disobeying Dr. Heinemann's orders to operate on the mayor is costly for Dr. Tenma. His career begins to plummet. The boy whom he saved finally awakens, but a horrible incident occurs soon after.

Things look brighter for Dr. Tenma, now that Dr. Heinemann is dead. His career takes off, and even Eva tries to win him back. But unfortunately, all that success has drawn the attention of Detective Lunge.

Adolf Junkers has information about the serial murders that is vital to the police, but he is afraid to reveal them. Dr. Tenma's care for Adolf Junkers however wins him over. His close relationship with Junkers however leads him to a night of shocking horror.

Nina Fortner, a talented young student in Heidelberg has been having nightmares. She also cannot remember anything about her life before she was 10 years old. She soon suffers from fainting spells in university and starts receiving anonymous emails.

Nina finally receives an email informing her to meet the anonymous sender at a specified time and place. Dr. Tenma in his search for the Liebert girl, asks Mauler, an editor for a local publisher, for assistance in his investigations.

Tenma and Nina return to the Fortners’ residence to find Mauler and Nina’s parents dead. Two detectives arrive to take them to the station for questioning, but certain things don't look right.

Eva tries to threaten Dr. Tenma, unless he gets back with her, she would reveal to the police that the tie that was found at the scene of the crime is his!

An old mercenary soldier named Hugo is interrogated by Lunge about a student of his, a doctor named Tenma.

Tenma encounters a burglar named Heckel who claims to have seen the killer. It soon results in Heckel leading Tenma to a couple of murderers.