In the fifteenth year of the Republic of China, there was an isolated island in the East China Sea.
A letter entrusted to him on his death bed extradited Peking police detective Lin Huaian here.
What awaits him is the death prophecy of the three sisters and a blood-sworn revenge that spans twenty years.
Blood Oath Island was a pirate lair in ancient times and a place of exile in the Qing Dynasty. The islanders believe in blood oaths - oaths written in cinnabar and evidenced by drops of blood. Anyone who violates this will be punished by God.
Before Shen Heting, the heir to the Shen family, died of illness, he appealed to his classmate Lin Huaian for help: his three sisters were dying. Lin Huaian rushed to the island, but it was too late - Shen's daughter Yuetang drowned on the seaside, holding a reed, and beside her was a famous line from the Book of Songs, "The so-called beauty is on the side of the water."
Strangely, the second daughter Yuetao later died among the fallen flowers, corresponding to Li Shangyin's "the east wind is powerless and all the flowers fade"; the third daughter Yueli disappeared, leaving only a white dress fluttering in the sea breeze.
The murderer killed people serially according to the imagery of classical poetry, leaving marks of "one, two, three" on the scene. The island is blocked by wind and rain, no one can leave it, and no one can come there.
In the deep house of the Shen family, there is the second uncle who has his own agenda, the cowardly third uncle, the mysterious old housekeeper, the maid of unknown origin... Everyone is a suspect, and everyone has their own secret.
Lin Huaian peeled off the cocoon and discovered that everything stemmed from a blood oath forgotten by the government twenty years ago - a woman who was abandoned in the beginning, an illegitimate daughter who died with hatred, and a family sin that was buried in the dust.
Blood debts must be repaid with blood, as a matter of course.
But who is qualified to rule? Who should pay the price?
When the truth surfaced, Lin Huaian understood: what the murderer wanted was never just revenge——
This was a trial that had been carefully planned for twenty years.
Intention: What is broken is not the blood oath, but the human heart; what cannot be repaid is not the blood debt, but the debt
