In Tsunoshima's Jukkakukan, a murder shocked every resident on the island.This case is different from usual because it involves a special group of victims-the laboratory ladies.They are the pride of the island, a group of young women full of wisdom and vitality.However, when one of their members is suddenly murdered, the originally harmonious team of laboratory ladies falls into deep suspicion and fear.

“Who is the culprit?”This question lingers in the minds of the laboratory ladies.Everyone begins to doubt their companions, and the originally close friendship becomes endangered overnight.They have to face a cruel fact: on this isolated island, they must find the murderer, otherwise no one will be able to leave after a week.

At the same time, the two detectives Jiangnan and Shimada also set foot on the land of Tsunoshima.They came to investigate another mysterious Aoyashiki incident.However, as the investigation deepened, they discovered that the two incidents seemed to be inextricably linked.

During the investigation, Jiangnan and Shimada met the gardener's wife Yoshikawa Masako.Masako Yoshikawa disappeared mysteriously after the Aoyashiki incident, and her appearance added more mystery to the entire case.Jiangnan and Shimada began to wonder whether Yoshikawa Masako was the key figure in the two incidents?

As the investigation deepens, the truth gradually emerges.It turns out that there is a huge conspiracy hidden behind the murder of the laboratory lady and the Aoyashiki incident.Masako Yoshikawa is the core figure of this conspiracy.In order to protect her secret, she did not hesitate to kill one of the laboratory ladies.

Under the ingenious reasoning of Jiangnan and Shimada, Yoshikawa Masako's crime was finally exposed.She was forced to admit her crime and was duly punished.The laboratory ladies also re-examined their friendship during this incident. They realized that unity and trust are their most powerful weapons when facing difficulties.