[Original Sci-Fi] Sea Traveler 2029

Apocalyptic rains flood the world. Li Shengwen wagers his life to transform into a merman, just to win his mother a ticket aboard an ark. Five years later, his younger brother Lin Zhisheng sets out from the underwater city with a gun, only to find his half-human, half-fish elder brother deep in the ruins. His tail is rotting, seeping a strange black mist, and he holds a shocking secret: extraterrestrial water is stealing Earth's water. His younger brother returns, bearing the truth, while the military's interrogation and the erosion of supernatural powers close in from both sides.

Theme: Survival in the apocalypse.