In the quiet apartment in Akiyama, Qing and reporter Ito explore the secret of death.Akiyama, the provider of information, seems to be involved in a more complicated mystery.When his girlfriend returns unexpectedly, the two are forced to hide in a closet and witness a murder disguised as a suicide.An assassin takes away the yellow flowers Akiyama hid, leaving more questions.

As the investigation deepens, Qinghe and Wanwei step into the domain of Yuantianhui.Here, they tried to find the clues left by Akiyama, but unexpectedly got involved in a ninja dispute.Riku, Akiyama's younger brother, takes a keen interest in Fuma Kotaro during the school's castle performance, and his mother Yoko is troubled by this.

Yoko was involved in a poisoning case of a cruise ship passenger by Hamajima of the Ninja Management Bureau.In order to obtain intelligence, she decided to sneak into the cruise company, but accidentally discovered that employee Kashiwagi was handling a suspicious passenger list.After interpreting Kashiwagi's lip language, she learned about Kashiwagi's connection with Matsuura.However, just as she tried to investigate in depth, Kashiwagi was assassinated.Yoko fights the killer, but eventually lets him escape.

All of this seems to be related to the mysterious ninja, and Nagi's experience makes the whole incident even more confusing.While returning the cultural relics, she was intercepted by a mysterious ninja and the cultural relics were stolen, leaving only a ninja sword as a clue.Although she successfully escaped the police pursuit, her younger brother Lu discovered something strange about her.

As the investigation deepens, Qing, Pianyou, Yangzi and Lu are all involved in a huge conspiracy.They must work together to solve this series of mysteries, find the truth, and at the same time neutralize the threat of ninjas.In the process, they not only have to face the murderer's pursuit, but also face their own inner fears and doubts.

In the end, with the efforts of everyone, the truth gradually emerged.It turns out that there is a huge ninja organization hidden behind all this. They are trying to achieve their own goals by manipulating the Yuantianhui and the tour boat company.Akiyama is a key figure in this organization, and the yellow flowers he left behind have become the key to revealing the truth.

In a thrilling decisive battle, Qing, Pingmei, Yoko and Lu successfully defeated the leader of the ninja organization and rescued the hostages.The police also arrived in time to bring the remaining criminals to justice.After the incident, Yoko confessed her experience to her husband Soichi and received his understanding and support.Riku also grew a lot through this incident and gained a deeper understanding of the world of ninjas.