According to legend, there is a "barrier" on the mountaintop of Sai Kung, which is a mysterious space similar to the Bermuda Triangle, causing many hikers to disappear mysteriously... After the police chief went hiking alone, he disappeared from the world. His daughter, who is a social worker, was upset and insisted on finding the truth, but she has been unable to find the truth for many years. When he was missing for seven years, a crazy hiking equipment store owner suddenly claimed that he had picked up the police chief's warrant card in the barrier on the mountain! The female social worker followed the legend of the barrier and was determined to find her father, but strange things happened one after another. The movie was adapted from a local online novel with over a million views, exploring the most mysterious legend of the barrier in Hong Kong. The familiar scenes of Sai Kung Hilltop and old public housing estates are integrated into the urban bloodbath in Hong Kong, which is chilling.