The mute girl Shen Zhao uses her notes as a sword to break into the Iron-Blooded Criminal Investigation Team. Every trace of blood she sees is the truth that has not been told. Captain Lin Xiao had to rely on this silent genius in order to clear the name of the old case. Forensic doctor Su Yan's autopsy report, police officer Chen Yu's precise calculations, and mysterious moderator Wen Yu's network manipulation formed a deadly web. When Shen Zhao finds the password left by his mother in a pile of old books, all the silent truths will begin to scream.
