Kenzo Tenma

A brilliant neurosurgeon who defies his hospital superiors to save a dying boy named Johan. Falsely accused of committing serial murders, he goes on the run from the authorities and is drawn into the “monster” and its mysteries.

Johan Liebert

A mysterious, handsome young man with an extraordinary intellect. His every action is carefully calculated. As a child, he suffers a severe head injury, but Tenma saves him. Is he the monster that Tenma is after…?

Nina Fortner / Anna Liebert

Johan's twin sister, also known as Anna Liebert. She is a gentle and kind-hearted college student who is loved by everyone. When a certain incident takes place, she joins the hunt for Johan and the truth behind the mysteries of the “monster.”

Eva Heinemann

The only daughter of the director of Eisler Memorial Hospital. She is Tenma's former fiancée. She cannot forget Tenma, even after breaking up with him. She feels both love and hatred for Tenma.

Inspector Lunge

A shrewd inspector from Germany's BKA [German Federal Criminal Police Office]. He believes that Tenma is a serial killer and steadfastly pursues him. He has an uncanny memory.