Rye has boarded a bus in Los Angeles to go to Pasadena, where she hopes to learn that her brother and nephews are alive. Buses are rare, and traveling is hard, but Rye is desperately lonely in a world from which language, written and spoken, has almost disappeared. Soon, two passengers start a conflict in gestures, postures, and noises. Other passengers watch anxiously, and the driver swerves to throw the men off balance. But soon they are fighting openly. When the bus stops, Rye exits the back to see a man pull up in a car, a rare sight. She watches as the large, bearded man gestures about what is happening on the bus. He wears an LAPD badge, yet the police department no longer exists. When he sees that a fight is going on, he tosses a tear gas canister into the bus, forcing everyone to evacuate. Rye helps some passengers while others gesture angrily at the bearded man. He ignores them but motions to Rye to come with him. Armed and suspicious, Rye tries to read his body language to guess what he wants.

As they communicate through gestures, passengers begin to stare at them. Since severely impaired people will attack those who show signs of intelligence, such communication is risky. A man gestures obscenely to suggest that Rye and the bearded man are sexual partners and that Rye should have sex with them. The bearded man lays his gun in the car’s seat and watches Rye, who decides that perhaps he’s lonely, as is she. The global pandemic that killed multitudes, including Rye’s family, left survivors with physical and mental impairments. Rye risks getting into the car, and they leave as men from the bus pelt the car with rocks. As they drive, they exchange objects that suggest their names—a piece of black rock, for the name Rye decides might be Obsidian, and a pin with a wheat stalk on it, somewhat close to the word rye.

The bearded man lets Rye point the way through the ruined city and then takes out a map on which Rye identifies the shape of Pasadena. When she realizes that Obsidian can read, a murderous jealousy briefly overcomes her. She had been a professor; now she cannot read or write. But she can speak and understand speech, which he cannot. Each has lost an ability vital to their lives and livelihoods.

Obsidian conveys a desire to have sex, but although Rye craves human touch, the dangers pregnancy would pose in their ravaged world are too great. However, Obsidian still has condoms. After they have sex in the back seat, Rye conveys to him that her three children died during the pandemic. She wants Obsidian to come home with her, but he declines. He needs to carry on with his duty as an officer. When Rye agrees that he can, he indicates that they are now a couple, and she feels happy and safer. But as they drive on, a woman dashes into the street in front of the car. A man follows her, yelling in fury and holding a knife. Obsidian goes to the woman’s defense, but the man stabs her before Obsidian can stop him. Obsidian shoots the man, who collapses but grabs Obsidian’s gun as Rye tries to tell him that the woman has died. The man kills Obsidian and turns the gun on Rye, who shoots him before he can fire again.

Stunned by the rapid changes in her life, Rye feels ill. Two tiny children go to the dead woman and try to wake her. Rye wants nothing to do with them because the world has no future for them. She pulls Obsidian’s body to the car to take it home for burial and decides to bury the woman, too. To her shock, the little girl says, “Go away!” The little boy scolds: “Don’t talk.” Rye realizes that these tiny children have the capacity to speak. Perhaps they were born with immunity. She picks them up to take them home, where she will teach and protect them. She assures them that they can safely speak to her, as long as no one is around, and tells them her full name, Valerie Rye.