Involuntarily Lynne began to shake her head in refusal, telling herself that Tony had chosen a very poor time to urge indulgence in lichenwasser. Then it occurred to her that her recent primness might have had something to do with the mysterious restlessness that seemed to be affecting all the members of the Depot. She said, “All right, Tony,” and drained the plastic tumbler. With the warmth of the drink she felt a soaring triumph. She was sure now that she had solved the problem of what was happening to the personalities of Nampura Depot. They _were_ in contact with some alien intellect, or mind, or personal force that reduced their complex human impulses to a few basic impulses and to basic impulse fulfillment. She said, “Tony, have you noticed anything peculiar going on around the Depot the last few weeks?” He thought it over, then nodded. “Two or three times I considered inveigling you into the supply room and making violent love to you, Lynne. I’ve had the impulse ever since I first met you at the New Samarkand Spaceport. But, _Crehut_, it was never like this.” “Give me another,” said Lynne, holding out her tumbler. “I forgive you for your candor. We should have kept behavior charts on everybody here, instead of just on the experiments. You’d better get psycho on it tomorrow, Tony. I’ve a feeling we’re in contact with that alien mind-force we’ve been looking for, and that it’s making like a psychological poltergeist.” “It’s just barely possible.” Tony looked thoughtful behind his spectacles. Then he said, “But if you’re right, and if Juan and Rana actually found it, _it can kill_.” Lynne looked somberly at the lichenwasser in her plastic tumbler. Then she said, “Yes, it can kill,” and drained it. III Lynne and Tony Willis were still discussing the problem when a somewhat haggard Rolf Marcein came in. Characteristically, he gave them no more than a perfunctory personal greeting. “I hopped the first transport after I got the flash, Tony. Lynne, what have you managed to find out about this ghastly mess?” “Nothing for the record yet,” Lynne told him, admiring and detesting simultaneously Rolf’s ability to dismiss all other relationships when a work problem arose. “But I’ve got a pattern of sorts.” “All right. Let’s hear it.” She went on to tell him, as concisely as she could, what she had figured out since her arrival. Rolf listened attentively, without comment, until she had finished. Then he frowned. “Tony, tell operations to set up the necro-recorder with the new psycho-muffler attached,” he said quietly. “We’re going to have to probe Rana’s mind while she’s still in shock. Otherwise, some of these Navajos will be trying their own _farbish_ experiments--and we may have a lot more corpses to worry about, or something even worse.” “Sure you feel up to it, chief?” Tony asked as he flipped a switch on his desk, preparatory to giving the orders.