Mermaid's Shelter

A chilling discovery. This is what the police thought when they found the mutilated bodies of three young women on the bank of the canal. They died at different times but ended up here simultaneously. There is a theory: the... bodies were carried here by a powerful current from a storm drain. The examination of the bodies led the police to conclude: this is the work of the same killer…
 
Busybody. Gu Hao, a former head of department security, has retired and is suffering from inactivity. But he doesn't have to be bored for long - his neighbor, a high school senior, disappears without a trace after not returning from a rehearsal for the school's premiere of the fairy tale “The Little Mermaid.” Hao is worried about her - and intends to find the girl at all costs.
 
Underground. Gu Hao's godson serves in the police and often shares information with him. The old serviceman suspects that the neighbor's disappearance and the bodies in the sewage system may be one case, albeit a very complicated one. He decides to go underground himself and find at least some trace of the girl - alive or dead…