The newcomers did not look like doctors, nor act like them. Visiphone contact with the landing grid was immediately broken. It could not be restored. So the isolated groups spoke agitatedly to each other by other visiphone contacts, exchanging messages of desperate hope. Then, new-landed men appeared at an apartment whose occupant was in the act of such a conversation with a group in a distant building. He left the visiphone on as he went to admit and greet the men he hoped were researchers, at least, come to find the cause of the plague and end it. The viewer at the other visiphone plate gazed eagerly into his friend's apartment. He saw a group of the newcomers admitted. He saw them deliberately murder his friend and the survivors of his family. Plague-stricken or merely terrified people--in pairs or trios widely separated through the city--communicated in swift desperation. It was possible that there had been a mistake--a blunder; an unauthorized crime had been committed. But it was not a mistake. Unthinkable as such an idea was, there developed evidence that the plague on Maris III was to be ended as if it were an epizootic among animals. Those who had it and those who had been exposed to it were to be killed to prevent its spread among the newcomers. A conviction of such horror could not be accepted without absolute proof. But when night fell, the public power-supply of the city was cut off--communications ended. The singular sunset hush of Maris III left utter stillness everywhere--and there were screams which echoed among the city's innumerable empty-eyed, unoccupied buildings. The scant remainder of the plague-survivors fled in the night. They fled singly, carrying the plague with them. Some carried members of their families already stricken. Some helped already-doomed wives or friends or husbands to the open country. Flight would not save their lives. It would only prevent their murder. But somehow that seemed a thing to be attempted. * * * * * "This," said Calhoun, "is not a history of your own case. When did you develop the disease ... whatever it may be?" "Don't you know what it is?" asked Helen hopelessly. "Not yet," admitted Calhoun. "I've very little information. I'm trying to get more now." What other information he had he'd gathered from a newly dead man in a field some miles away. He did not mention that at this moment. The girl went on, exhaustedly. The first symptom was listlessness, of which the victim was unconscious. One could pull out of it with an effort, but one wasn't aware that anything was wrong. The listlessness progressed. One could realize it only by recognizing the more urgent, more violent effort needed to pay attention, and the discovery of weakness when one tried to act. One did not feel discomfort--not even hunger or thirst. One had to summon increasing resolution even to become aware of the need to do anything at all.