Ten years after her arrival, Helena, now married to Domin, prepares to celebrate her anniversary. Despite the festive gifts from the factory’s administrators, the mood is tense. Across the globe, robots have begun to revolt, killing thousands of humans. News from the outside world brings only dread.

As Helena speaks with her robot servant, Nana, she recalls how the problems began when Dr. Gall, one of the chief engineers, reprogrammed the robots to feel pain in an attempt to improve their efficiency. However, this gave rise to unintended consequences—robots started resisting their roles and became more dangerous, especially a prototype named Radius, who now advocates for robot rebellion.

Despite attempts to restrain Radius, his influence spreads. Helena is further unsettled when Domin offers her a gunboat for pleasure cruises, though she now fears for her life. When Helena and Nana read a smuggled newspaper, they learn of the robots’ massacres and a disturbing decline in human birth rates. It seems humanity has lost its will to survive.

Dr. Gall arrives with Radius in tow. Gall wants Helena’s permission to dispatch Radius to the stamping-mill. Helena, intrigued by how the robot has developed feelings and seems now capable of independent thought and self-preservation, denies the request.

Helena talks to the robot directly. “Radius, Dr. Gall gave you a better brain than the rest, better than ours. You are the only one of the Robots that understands perfectly.” Radius resists her compassion and boldly says he only wants to be the master of humans. Dr. Gall threatens Radius with the stamping-mill. “There they’ll kill you. They will grind you to powder. That’s terribly painful, it will make you scream aloud.” Radius condemns Gall’s lack of humanity.

Helena asks Gall about the newest female robot that would reflect the latest programming efforts to mimic human characteristics. The robotess is ready, he says. He has named her “Helena.” The only problem, Gall tells her, is that robots wear out after ten or so years, and they have no way to reproduce themselves because they have no access to Rossum’s original research.

Alarmed and hoping to end the growing robot threat, Helena decides to burn Dr. Rossum’s original research, which contains all the formulas for robot production.
The contingent of facility administrators then arrives. They anticipate the arrival of a mail boat, hoping for reassuring news. However, they understand that they may need to negotiate with the robots to avoid an open rebellion. They propose offering Rossum’s secret formulas, giving the robots the power to recreate themselves.

Even as they head to the dock, the administrators discover the robots have sabotaged the island’s telephone lines and radio station, cutting the island off from the world. In the face of imminent threat, Domin, ever the optimist, theorizes converting factories worldwide to produce robots corresponding to different ethnicities with different skin colors and languages. Over successive generations, he predicts, these robots will start fighting each other, will hate each other just like people, and then they will need humans to restore peace. The idea seems far-fetched.

Far from bringing good news, the mail-boat is full of robots who, using inflammatory handbills proclaiming humanity as the enemy, quickly spread the revolution to the island’s robots. The administrators barricade themselves into the headquarters office. Desperate to protect themselves, they activate the island’s security fence, electrifying the railings around the compound.

They hear the factory whistle suddenly blow. They hear the menacing approach of the robot mob. They pull shut the iron shutters over the windows. The robot attack has begun.