Can Johan have a split personality, like Jekyll and Hyde? Tenma calls in Dr. Gillen, an expert in criminal psychology, to analyze Johan. However, Dr. Gillen secretly concludes that it is not Johan, but Tenma who has committed all the serial murders. Dr. Gillen then tries to trap Tenma in various ways in order to use him in his own experiments.

Karl, a student at the University of Munich, visits a blind billionaire every week to read books to him as a way to pay for his studies. One day he meets another young man named Johan, who had done the same job for the billionaire. From that moment on, strange events continue to happen to Karl. Who is this young man named Johan? Is he the Johan we know?