The protagonist Lin Shen, a psychiatrist with extraordinary talents but troubled by nightmares, discovers that he can "sneak into" the psychological world of his patients. There, the disease turns into a concrete maze, monster or strange rules. He must go on an expedition to find and resolve the core trauma in order to heal the patient. Every time he succeeds, he can permanently acquire a unique ability in the psychological world of the disease (such as the "absolute order" from obsessive-compulsive disorder, the "emotional flame" from bipolar disorder), but this power is also quietly changing himself.
I like this psychological novel very much