Monster: Perfect Edition, Vol. 1 (Kanzenban #1) by Naoki Urasawa (Creator), Camellia Nieh (Translator)

Dusseldorf, Germany 1986. Germany is still divided into two parts. Dr Kenzo Tenma is a successful neurosurgeon at Eisler Memorial Hospital. He had just performed a successful operation on a famous opera singer, but the credit was taken by the director during the press conference.

Later he found out that he was supposed to be treating a Turkish construction worker injured in an accident instead of the opera singer. Dr Tenma feels that if the Turkish construction worker had been treated sooner, he would still be alive.

Meanwhile, a trade advisor who recently defected to the West with his family has been killed but survived with a daughter and son. The son Johan is in a critical state, and Dr Tenma received an emergency call to treat the boy. At the same time, the mayor is admitted to the hospital and requires urgent treatment. The director arranged the best team to work with Dr Tenma to treat the mayor. Dr Tenma faces a dilemma but ultimately makes a conscientious decision. His courageous action leads him to the beginning of his life's falling, including his once highly reputable career. As he is struggling with the demotion and the failed relationship, three doctors are killed, and the twins (the defector's children) are missing at the same time.

In 1995, another middle-aged couple was murdered. It is the fourth case in Germany in the past two years. All of the victims share one common thing, which is childlessness. While the BKA is investigating the case, their suspect Herr Junkers is hit by a car. He almost lost his life but was saved by Dr Tenma.

Herr Junkers reveals part of the truth to Dr Tenma, but before he starts his confession, he flees from the hospital, following an unknown figure. Dr Tenma chases after him and discovers the unknown figure is not someone he ever expected would be the killer. The killer is someone who used to change him to become a better doctor with a conscience. But now, that person has a nickname called "Monster".