Darden and Catherina, two Black Americans who have received body modifications, set sail on vehicles called Mules that will take them to an underwater colony off the coast of South Carolina. The two lovers are also involved with a touring band that intends to perform in the colony.

In a transcript of an interview from a few years ago, a politician insists that the body modification process will be incredibly lucrative.

Darden and Catherina break the surface for air and believe they spot white supremacists on the horizon in a helicopter. Their right of way to travel to the colony will expire soon.

Catherina is hit by a poisoned dart shot by a white supremacist and goes unconscious, but the two are rescued by Joa, a man who lives near the bottom of the sea. He takes them to a sunken train car; he and Darden can communicate through the water via headsets.

In another interview transcript, a white supremacist group explains why the underground colonies are dangerous. It promotes the idea that a modified man sexually assaulted a woman, though this is a complete lie. Darden, Catherina, and Joa reached an entire community of others like them and set up for their band's performance. In the middle of the concert, an attack comes from the surface, and one band member is killed in front of Darden. Metal jaws destroy the seating area. Catherina and Joa manage to escape. Darden finds out that, for some reason, his and Catherina's headsets have been turned off.

In another transcript, two unidentified parties say that they rigged the two headsets to carry secret frequencies. Later, Darden speaks with an official representative and tells her he wants to live like Joa, showing newcomers around the community. He says that he believes white people should be able to visit and come see the band's shows. He says that the two groups want some of the same things, even if they are enemies.