She then fires another flare at the shark, setting the oil from the whale carcass alight and angering it, but otherwise having no effect. She shoots one flare to draw the attention of a faraway cargo ship, but the ship has already turned away and does not see her. After sending Steven Seagull toward shore on a piece of the surfboard, and timing the shark's circles from the whale carcass to the rock, Nancy swims to a nearby buoy, narrowly avoiding the shark by swimming through a group of jellyfish, which sting both the shark and her. With high tide approaching, Nancy realizes the rock will be submerged soon. Nancy uses the GoPro to leave messages for her sister and father as well as information about the shark attack and her location.

After some struggle, she is able to retrieve it and notices in the footage of the attack, the shark has a large hook stuck in its mouth after a possible encounter with fishermen. Nancy later sees the helmet floating in the water.

When he was attacked by the shark, his helmet had come off and floated to the surface. One of the local surfers was wearing a GoPro camera on his helmet. They get into the water before Nancy can warn them away, and are also killed by the shark. Several hours later, the two locals Nancy had surfed with the day before return. While wading out into the shallow water to steal Nancy's surfboard, however, he is killed by the shark. The next morning, a drunk local man on the beach steals Nancy's belongings. Nancy is left alone when the unaware locals leave the beach, and she spends the night on the rock with a wounded gull, which was also injured by the shark, and names him Steven Seagull. Later she uses her jewelry to put rudimentary stitches in place to hold her torn flesh together. She uses her surfboard strap to slow the bleeding from her leg. Nancy climbs onto the whale carcass, but the shark rams it from underneath, forcing her to swim to an isolated rock. As she rides the last wave back to the beach, a large great white shark knocks her off her surfboard and bites her leg. While surfing one last time for the day, Nancy notices the carcass of a young humpback whale nearby. When she talks to her father in an emotional and strained conversation, it is revealed that her mother's death caused Nancy to consider dropping out of medical school. Taking a break from surfing, Nancy video-chats with her younger sister Chloe. Nancy joins two other locals and the three surf for several hours. Carlos, a friendly local resident, gives Nancy a ride and drops her off at the beach, while a friend of hers who came along with her is staying back at a hotel after partying too much. Shortly after the death of her mother due to cancer, medical student Nancy Adams travels to a secluded beach in Mexico, the same beach her mother visited while she was pregnant with her.

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