In the "Era of Eternal Night" when the sun goes out, the former memory examiner Shen Mo chooses to become the guardian of the lighthouse on an isolated island in the "Sunless Sea" in order to escape the bloody past. The former guardian disappeared mysteriously, leaving only a logbook filled with crazy rants. When he investigates deeply, he discovers that this ancient lighthouse that swallows light and sound seems to have an eerie resonance with the memories he buried with his own hands. A man who firmly believes that everything is logical is forced to listen to the whispers from the abyss in a forgotten corner and face the truth that science cannot explain.
