On the first day of school, a Chinese teacher jumps to her death. A red Queen card is nailed into her palm. The card's return brings the horrific serial murder case from five years ago back to life. A senior superintendent is caught up in suspicions of perjury; criminal gangs repeatedly enter the public security bureau; a strange virus appears on the Yunnan border; and countless human Gu are imprisoned in a lightless basement. Just when they think they have everything under control, they realize they are already mired in a quagmire. Amid the tangled cases and relationships, an even bigger secret lies hidden...
