World War Terminus has left the Earth a radioactive wreck. Most survivors have emigrated to Mars, where the authorities promise them an easy life with android servants. Only those too poor to emigrate, or who have been genetically damaged by radiation (the chickenheads), remain on Earth. They huddle in scattered population groups; use mood organs that allow them to predetermine how they will feel each day; follow Buster Friendly, who is on television and radio twenty-three hours a day; and practice Mercerism, a universal religion that teaches empathy and community-feeling through repeated images of an old man struggling to climb a barren hillside. Animal life has been more severely affected by the war than has humankind, so social status in this bleak postapocalyptic world is determined by keeping an animal; those who cannot afford an animal keep a robot simulation.

Rick Deckard is a bounty hunter whose job is to retire (kill) androids who attempt to escape their servitude on Mars. He and his wife, Iran, have an electric sheep, but they dream of being able to afford a real animal. Deckard gets his chance when six Nexus-6 androids escape to San Francisco. The Nexus-6 is the most advanced android to date, indistinguishable from humans, and it is not at all clear that the standard Voigt-Kampff Empathy Test for identifying androids will work on them. So Deckard must first visit the manufacturers. The first individual on whom he tries the test, Rachael Rosen, seems to come out as human, but Deckard is suspicious and asks her one last question. Her answer reveals that she is indeed an android. Rachael then offers to help him hunt down the escaped androids, but he rejects her offer.

The first android is masquerading as a Russian police officer, but Deckard sees through the deception and kills him. The second is a singer with the San Francisco Opera, but before he is able to administer the Voigt-Kampff test, she has him arrested. Though himself a police officer, Deckard is taken to a station he does not know, which is staffed by police he does not know and who do not know him. When he tries to phone out, he cannot contact anyone who recognizes him. It turns out that the entire happening is an elaborate front set up by the third of the androids. With the help of another bounty hunter who is not sure whether he himself is an android or a human, Deckard is able to kill the android and escape from the fake station. The two bounty hunters then return to the opera and shoot the other android. The bounty from the three androids he retired gives Deckard enough money to buy a real goat.

John Isidore is a chickenhead who does not meet the minimum intelligence standards for emigration. He works as a driver for an electric-animal repair center and lives alone in an abandoned apartment block. He soon finds someone else living in the same building, a young woman called Pris who seems scared of everything. Isidore tries to befriend her, though she treats him with disdain. Later, two of her associates, Roy and Irmgard Baty, show up; Pris, Roy, and Irmgard Baty are the three remaining Nexus-6 androids, though Isidore does not recognize them as such. The three use Isidore to fetch and carry for them as they take over his apartment as a hideout, but though he recognizes that he is being exploited he still relishes the companionship. Then Isidore discovers a live spider, and Pris tortures it by cutting its legs off one by one, and at...