"The Long Corridor," a best-selling suspense novel by Keigo Higashino, serves as the basis for this film. It revolves around a cloister pavilion mansion that harbors countless secrets, where a woman's vengeful desires are ignited by love. The death of a wealthy businessman prompts his relatives to gather in the mansion, waiting to claim their share of the billions in inheritance. Each person carries their own hidden agenda. Just when the situation becomes critical, lawyer Zhou Yang arrives with a will and a mysterious diary, shedding light on a year-old arson and murder case. Shockingly, the deceased was the wealthy businessman's illegitimate son living abroad, making him the sole heir of the entire estate! The murderer lurks within the crowd, evading detection.
Following the death of a wealthy merchant due to illness, a year-old case of arson and murder came to light, implicating the first heir of the estate, who happens to be the deceased’s illegitimate son, thus complicating the distribution of the assets.