《Southern archives》Episode 15 merges the depths of the archives with Zhang Haiqi's pursuit line.Lu Junxiang led his troops into the secret passage where Zhang Haiqi was hiding, but they ran into a Maxim machine gun trap set by her and the musketeers. The soldiers suffered heavy casualties.Lu Junxiang was unwilling to fail and used dusk grass seeds to fight back. The Musketeers were overwhelmed by the poison, and Zhang Haiqi could only escape with difficulty.She knew that Lu Junxiang would not stop, and she also knew that after the archives' defenses were activated, the seawater poured in and everyone might be trapped underground.

At the same time, Zhang Haiyan discovered a cavity in the deepest part of the archives. The marks inside were consistent with the symbols left by Zhang Haixia.He recalled Zhang Haixia's earlier talk about the origin of danger symbols, and saw a giant chain leading to the deep sea. The notes on the side recorded that agents had collected antidote ingredients at the bottom of the sea.The last medicinal ingredient was underwater, but diving meant there was almost no way out.Zhang Haiyan no longer wanted to lose Zhang Haixia, so even though he knew the danger, he still jumped into the sea and searched desperately downwards.The lack of oxygen, injuries and water pressure quickly pushed him to the limit. Before he was about to die, he was rescued by Zhang Haiqi who arrived.

Zhang Haiqi also had a head-on confrontation with Lu Junxiang before, severely injuring the opponent with her absolute strength. Then the tunnel collapsed and Lu Junxiang was buried.After she brought the seriously injured Zhang Haiyan back, she revealed to him the truth about the Southern Archives and the reason why the Zhang family is strong and longevity.Zhang Haiqi used special herbs to treat Zhang Haiyan's injuries. After Zhang Haiyan woke up, his body transformed, and his strength and tolerance were significantly enhanced.In order to retrieve the last medicinal ingredient, he dived into the deep sea again, and this time he finally succeeded.After the medicinal materials were handed over to Zhang Haiqi, she began to prepare the medicine to treat Zhang Haixia, and Zhang Haiyan also fell into a coma due to dehydration.When he woke up, the three masters and apprentices reunited in the old home of the Zhang family, and Zhang Haiyan truly stepped into the core secrets of the Zhang family and the archives.

This episode is not only the completion of the medicine collection test, but also the node where Zhang Haiyan’s identity changes.In the first few episodes, he has always regarded himself as someone who owes Zhang Haixia, and his actions are almost completely driven by the word "rescue"; in the 15th episode, he was led into the secrets of the Zhang family by Zhang Haiqi. After his body was transformed by herbal medicine, he was able to dive into the deep sea again.Lu Junxiang was severely injured, the last medicinal ingredient was obtained, and Zhang Haixia was rescued. Many crises were temporarily resolved, but the Southern Archives revealed more secrets.Zhang Haiyan is no longer just a detective who stumbled into an old case. He has personally experienced the core mechanisms of fake death medicine, archives defense, and the Zhang family's physique.The reunion of the three masters and apprentices was filled with the warmth of the aftermath, which also meant that a new identity and deeper responsibilities had officially fallen on him.Zhang Haixia's awakening allowed Zhang Haiyan to respond to the sacrifices made in the previous episodes, and also allowed Zhang Haiyan to truly complete the transformation from self-blame to responsibility.