Proofreader Lu Yan used a proofreading book full of red pen annotations to uncover five seemingly unrelated murders one after another. Behind every typo on the page are testimonies that have been deliberately erased. Shen Yao, the leader of the serious crime team, discovered that all the deceased had access to the same out-of-print file during their lifetime. The real fatal thing is not the murder, but the changed punctuation - they silence the truth forever. When the deaf-mute printer Zhao Ya used ink to draw the thirteenth period on the wall, Lu Yan finally understood: someone was using words to systematically kill memory.
