After the oceans rise, food becomes scarce, prehistoric ocean creatures return, and people evolve in horrifying ways. Mir remembers the day her mother carried her brother into the sea. He’d been born with many sets of gills, and her mother feared what he would become. They both drowned. Now Mir lives alone with Papi, often visiting Jersey, the only boy who lives near her, for sex and companionship. But Mir’s world cannot last; Jersey wants to go inland and find a less desolate life, while Papi begs Mir to stay with him as the mutations wracking his body run their course.

As Papi transforms, he hungers for Mir’s flesh. One day, he tricks her into joining him at the water and tries to have sex with her and then eat her. Mir fights him off, ultimately killing him, and joins Jersey to move inland. She secretly harbors her own fears—for Mir has gills like her brother’s, like Papi’s, and she cannot remain human forever.

She and Jersey hope to find civilization, but they only find a newly formed lake. They build a home on its banks, and Mir gives birth to fish-children. As she lies beside Jersey each night, she forgets her love for him, and even his name. She regards him as the Food and waits for the day when she is ready to consume him.