One afternoon, the protagonist Fang Zhe receives a package in which the clues points to his mother who have been missing for many years. Recurring nightmares, horrifying whistles, letters from many years ago... Fang Zhe embarks on a strange adventure to find the truth.

One afternoon, the protagonist Fang Zhe receives a package in which the clues points to his mother who have been missing for many years. Recurring nightmares, horrifying whistles, letters from many years ago... Fang Zhe embarks on a strange adventure to find the truth.