He saw the little girl who'd come out of the airlock last of all the passengers. She sat on a sofa as if someone had told her to wait there until something or other was arranged. Doctor Nordenfeld barely glanced at her. He'd known Jensen for a considerable time. Jensen had been a passenger on the _Star Queen_ half a dozen times, and he shouldn't have been upset by the temporary stoppage of an interplanetary drive. Nordenfeld divided people into two classes, those who were not and those who were worth talking to. There weren't many of the latter. Jensen was. He filed away the health slips. Then, thinking of Jensen's pallor, he asked what had happened to make the _Star Queen_ interrupt her slow-speed drive away from orbit around Altaira. The purser told him. But the purser was fussily concerned because there were so many extra passengers from Altaira. He might not be able to take on the expected number of passengers at the next stop-over point. It would be bad business to have to refuse passengers! It would give the space line a bad name. Then the air officer stopped Nordenfeld as he was about to join Jensen in the fourth-level bar. It was time for a medical inspection of the quarter-acre of Banthyan jungle which purified and renewed the air of the ship. Nordenfeld was expected to check the complex ecological system of the air room. Specifically, he was expected to look for and identify any patches of colorlessness appearing on the foliage of the jungle plants the _Star Queen_ carried through space. The air officer was discreet and Nordenfeld was silent about the ultimate reason for the inspection. Nobody liked to think about it. But if a particular kind of bleaching appeared, as if the chlorophyll of the leaves were being devoured by something too small to be seen by an optical microscope--why, that would be chlorophage. It would also be a death sentence for the _Star Queen_ and everybody in her. But the jungle passed medical inspection. The plants grew lushly in soil which periodically was flushed with hydroponic solution and then drained away again. The UV lamps were properly distributed and the different quarters of the air room were alternately lighted and darkened. And there were no colorless patches. A steady wind blew through the air room and had its excess moisture and unpleasing smells wrung out before it recirculated through the ship. Doctor Nordenfeld authorized the trimming of some liana-like growths which were developing woody tissue at the expense of leaves. The air officer also told him about the reason for the turning off of the interplanetary drive. He considered it a very curious happening. The doctor left the air room and passed the place where the little girl--the last passenger to board the _Star Queen_--waited patiently for somebody to arrange something. Doctor Nordenfeld took a lift to the fourth level and went into the bar where Jensen should be waiting.