Two divers found the wreckage of Quint’s boat and were killed when taking pictures. The next day, Police Chief Martin Brody received a report that someone had discovered an unmanned yacht in nearby waters. Brody assigned his deputy Hendrix to investigate and retrieve the missing person's underwater camera. At the same time, Terry, a woman who was water skiing, was buried in the belly of the fish. The woman driving the speedboat threw the fuel tank at the shark and ignited it with a flare gun. The shark burned, and the speedboat was also torn apart in the explosion, but was seriously injured. The shark escaped. Because he could not find the remains of the victims, Brody began to have doubts.
An orca stranded on the beach. Brody speculated that it was caused by a shark attack. Although marine biologist Alkins was skeptical, she admitted that sharks are attracted to blood, movement, and sound. Brody thought there might be another great white shark, but Mayor Vaughan warned him not to be alarmist. Brody later discovered the wreck of the speedboat and the charred driver's body. That night, he injected cyanide into the warhead.
A few days later, Brody found on the observation tower that the shadows approaching the bathing beach looked like great white sharks. He ordered everyone to go ashore immediately and shoot at the water. This caused the crowd to panic, but it turned out to be a false alarm. The shadow turned out to be a school of herring swimming on the beach. Brody obtained the camera film of the missing diver, and a close-up of the shark's eye appeared in the picture. This confirmed Brody's guess. He immediately rushed to inform the mayor and others, but they still believed that the evidence was not reliable enough. The town’s tourism industry was in a period of recovery. The local executive and developer Peterson was unwilling to miss the opportunity, so he fired Brody in a fit of anger.
Early the next morning, Brody's two sons sneaked out of the house and sailed. They met a group of children learning to dive at sea. The diving instructor spotted the great white shark as soon as he got out of the water. A thrilling killing and attack began. At the same time, Brody noticed that an ambulance was speeding to the dock. An ominous premonition came to life. Brody drove right behind and found a diving instructor with an air embolism on the beach. After learning that their two sons and other children were still trapped at sea, Brody and others immediately sailed out to rescue them.
The Coast Guard helicopter was the first to spot the children floating on the sea with the help of broken sailboats. Just as the pilot was about to drag them back to the shore with ropes, great white sharks suddenly appeared, and the helicopter with damaged floats immediately sank into the water. The children floated to the island where the power transmission station was built, and the great white sharks were also in hot pursuit. Brody, who arrived in time, had an idea and tried to get rid of the great white sharks with cables. After a desperate contest, the great white shark who bit the cable was finally unable to withstand the electric shock.
