During an investigation into the Cas Group, Qin Yu's fiancée died a bizarre death. Hoping to bring this heinous bio group to justice, Qin Yu followed Jason, who had evidence of the group's crime, on the cruise. They were suddenly attacked by a group of mutant snakes and ended up on the island where the Cas Group was conducting illegal experiments. The strange ecological environment of the island and the second attack of the giant mutant snakes plunged Qin Yu and the others into a deadly crisis. As a team, they worked together to escape and successfully expose the evil doings of the Cas Group to the world.