Gambling: the Overwatch Game

Under the neon lights of the bustling city, there is a bloody rule that has lasted for three hundred years. The three major families, K, Q, and J, control the underground lifeline of the city. Each family is divided into hierarchies based on playing card numbers, maintaining a delicate balance in the midst of indulgence and wealth. Until overnight, K-6, the patriarch of the K family, died tragically in the secret room. A hole was opened in his chest and his heart was missing. Only four blood-stained playing cards were left on the scene - the King of Spades, the Queen of Hearts, the Jack of Clubs, and the Ace of Diamonds. Is this a vendetta? Is it a warning? Or some kind of ritual sacrifice? A-7, a newcomer to the Special Case Investigation Bureau, was ordered to intervene in the investigation. He soon discovered that this was not a simple murder case - the backward clock on the wall, the corroded surveillance hard drive, DNA from an unknown species, three hundred years of sacrifice ledgers... Every clue pointed to a deeper mystery. Lin Wan (Q-8 of Hearts), the mistress of the deceased K-6, seems to be cooperative, but she hides secrets everywhere; representatives of the three major families have their own agendas and blame each other; the missing K-5 corpse floating in the river died in the same way; and A-7 himself was involved in a death game called "Fighting the Landlord". When the clock strikes midnight, when "that thing" emerges from the shadows, and when A-7 discovers that the darkest secrets of the three families are hidden behind his life experience - he must answer one question: Who is the landlord in this card game that lasts for three hundred years? Who are farmers? Who is controlling everything? And who does the blood-stained Ace of Diamonds represent?