The sea is mysterious. It breeds life and hides many unknown things. People are not yet alert and continue to destroy nature with civilization, which will be counterattacked by nature. Rescue team member Ajie (played by Wang Yangming) and his companions rescued a reef-struck oil tanker in a storm, but encountered a captain who was stubborn and unwilling to give up. At the same time, a dark shadow emerged from the deep sea and dragged everyone into the sea. The surviving Ajie has been burdened with the shadow of his colleague's death and has become decadent and discouraged. Many years later, Ajie overcame the shadow and boarded the fishing boat again, but was constantly provoked by crew members Atai (played by Zheng Renshuo) and deputy captain Ading (played by Li Liren). One day, everyone rescued Xiaojing (played by Ke Jiayan) who fell into the sea due to the capsizing of the yacht. The boat changed subtly because of Xiaojing's intrusion. Accidents began to occur frequently on the boat. Some people fell into the sea and disappeared, some died accidentally, and food and drinking water were destroyed. Because of the space oppression and lack of air and food in the cabin, people began to clamor and panic, and they changed from supporting each other to self-suspicion. When the trapped people face the severe test of the storm, they find that the most dangerous thing is far more than that. There are unknown creatures under the water coveting them... The people who are facing each other fiercely must put aside their prejudices and work together to survive.