Survival in the sewers.
Hippo-Ho: An invention by Dr. Brain shaped like a bacteriophage that can shrink to a nano-scale. Plot Progression: 1. Gu Suri sneaks into Dr. Brain's lab and boards the Hippo-Ho. 2. Gu Suri presses the shrinking button on the Hippo-Ho, reducing it to nano-size. 3. The Hippo-Ho is flushed down a toilet and enters the sewers. 4. Meanwhile, Pipi arrives at Dr. Brain's lab. 5. Pipi asks Dr. Brain where Geo and Kei are, but Dr. Brain says they are in the annex. 6. Dr. Brain senses something is wrong, checks the CCTV, and attempts to track and rescue the Hippo-Ho (with Pipi joining). 7. Kei and Dr. Brain make a video call to share their location, but Kei says it's difficult because they are inside the sewer. 8. However, after seeing the village map drawn by Gu Suri, Kei succeeds in piloting the Hippo-Ho to escape. 9. Geo tries to press the enlargement button on the Hippo-Ho, but it malfunctions. 10. After exiting the sewer, the Hippo-Ho falls into a storm drain. 11. The rainwater makes controlling the Hippo-Ho difficult, causing Geo to struggle. 12. Meanwhile, Pipi and Dr. Brain track the Hippo-Ho and drive toward it. 13. Currently, the Hippo-Ho narrowly manages to get outside and clings to someone's clothes. 14. It then gets stuck to a car's side mirror. However, that car crashes into a tree. 15. The impact causes the Hippo-Ho to fall back into a sewer drain. 16. The Hippo-Ho passes through a sewage treatment facility and ends up in a stream. 17. Dr. Brain and Pipi use an enlargement device to return the Hippo-Ho to its original size. 18. Kei, Gu Suri, and Geo exit the Hippo-Ho. 19. The user continues the story from here!
Early teens Male
Early teens Female
Early to mid-20s Male
Mid-40s Male
Early teens Female
Gu Suri sneaks into Dr. Brain's lab to look around but gets caught by Geo.
Prove that you're a reporter! You could be lying for all I know.
Here, look for yourself. She holds out a business card.
Release Date 2026.09.26 / Last Updated 2026.09.26