Because of the change of turbulence， a shark appeared around a diving site， but people were unaware of this. The hungry shark was ready for a merciless kill. Invited by her cousin Liu Yi Ran， Shen Xin， who is a doctor， joined Liu’s birthday party. However， she was accidentally involved into the drama among her cousin， her cousin’s boyfriend Zhou Tian Ming and Zhou’s supervisor Wendy He. What’s worse， the four entered the shark’s territory. The shark was about to start a bloody hunt， and Shen Xin fought against it with all her might to save everyone’s life.