I, King of Criminal Investigation, Solving the Rainy Night Serial Murders from the Beginning.

Summary

Summary of the text: Police officer Guan Feng and his team investigate a homicide case by visiting a nail salon called Lan Kai. They discover a distinctive scythe design on the salon's wallpaper that matches a crucial piece of evidence from the crime scene. To gather more information, Guan Feng and his colleague Huang Li Li pose as a couple seeking a manicure, engaging the salon's staff in conversation while subtly investigating the potential connection to the murder case.

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