In Gyeongseong Creature, a Japanese soldier uses a parasitic organism, Najin, to create powerful creatures.
The events of Gyeongseong Creature take place in 1945. In the show, during the Second World War, the Japanese are looking for ways to win the war.
For that, as well as to test the limitations of human anatomy, various experiments are conducted on the people of Japan’s colonies.
The experiments and research lead to the discovery of a parasitic organism called the Najin. It is found deep in the glaciers of the Muryong Mountains.
Kato, a high-ranking Japanese soldier who possesses the Najin, believes that the parasite will evolve humans, as it has regenerative powers.
Additionally, he uses the organism to turn humans into formidable weapons for his country.
Human experiments
Kato chooses his test subjects from the people that the Japanese Army imprisons. The chosen subjects are made to consume the Najin, a tiny organism.
Once the Najin enters the human body, it takes complete control of the brain. Under the Najin’s control, the human body starts mutating.
However, after consuming the Najin, not all humans survive. The few who do survive are given a serum that changes them forever.
Their bodies become bigger and stronger, but not without a cost. The person who has consumed it transforms into a creature that no longer resembles a human being.
This creature can easily hunt humans and kill them within seconds. It is impervious to bullets, and the only way to kill it is to burn it.
Light weakens it, and Nitrogen is used to put it to sleep. What is strange is that even when the creature is asleep, it releases spores that kill humans when they come in contact with them.
If the serum is not administered after consuming the Najin, the person only turns into a predator but retains their human form; they do not turn into a monster.
They become stronger and more aggressive. Apart from gaining the ability to heal their wounds instantly, they are able to analyze situations quickly like a predator.
They are controlled by the parasite, and it makes them hunt human brains to survive. As Myeong-ja was not injected with the serum, she never turned into a creature like Seishin.
The creatures in Gyeongseong
Kato had succeeded in creating a creature using the Najin but was forced to burn it to death when the Japanese were given orders to retreat.
He then continues his experiments in Gyeongseong. He puts the Najin in Seishin’s water. She is then injected with the serum, which turns her into a powerful creature.
She is trained by the director of Ongseong Hospital to be used in war. However, she is more intelligent than they thought and ends up taking the lives of several Japanese soldiers.
Furthermore, it turns out that humans do not lose themselves entirely after Najin takes over their brains.
When Kato tries to get the creature to kill Chae-ok, she calls the creature mother, which leads to the creature recognizing her as her daughter and protecting her from other soldiers.
This time, even with nitrogen, the soldiers find it difficult to control the creature because its maternal instincts overpower the Najin.
Since Chae-ok’s mother was successfully turned into a creature after consuming the Najin, Kato tries to get Chae-ok to consume it.
While Kato fails, Chae-ok’s mother later feeds her a fully-developed Najin to bring her back to life.
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