London, 1899, but not the London you know.
Here, the Thames hangs upside down in the sky, steam trains travel between the clouds, and the entire city is enveloped by a huge transparent dome - a device called the "Amber City" that seals humanity's last refuge outside of time.
Ethan, a seventeen-year-old mechanic apprentice, comes into contact with forbidden knowledge from the "Upside Down Sea" due to an accident, and his shadow begins to have its own consciousness. At the same time, cracks appeared in the protective barrier on the edge of Amber City, and the "unspeakable things" outside the city were ready to move.
When everyone thought the crack was a mechanical failure, only Ethan discovered that it was an "invitation" deliberately created by some kind of existence. As the investigation deepens, he is forced to be involved in a conspiracy that spans three centuries: the Amber City itself is not a sanctuary, but a giant cage. Human beings are trapped, not because there are monsters outside the city, but because the humans themselves within the city have become monsters.
Now, the Hanging Sea is about to overturn, and Amber City's time is about to run out. Ethan must make a choice before the city falls into eternal madness: repair the barrier and continue the lies, or break the amber and face the bloody truth?
