Five years ago, the grandfather of Lin Xuan, a descendant of a family of traditional Chinese medicine, died suddenly and mysteriously. The last page of the ancestral secret book "Thirteen Needles of the Ghost Gate" disappeared. He only got a simple copper needle engraved with the word "Ghost Gate".
Five years later, Lin Xuan, who has become an ordinary forensic doctor, assisted the police in investigating a series of bizarre death cases. He discovered that all the deceased had a strange pinhole that could not be detected with a silver needle. His technique pointed to the long-lost "Ghost Gate Acupuncture Technique".
