"I should have said, Partner Elijah," said Daneel, speaking suddenly, "that that is an obvious conclusion."

Baley cast a surprised look at his robot partner. "Why obvious?" he asked.

"The lady herself," said Daneel, "states that she was the only person who did or who would see her husband. The social situation on Solaria is such that even she cannot plausibly present anything else as the truth. Certainly Agent Gruer would find it reasonable, even obligatory, to believe that a Solarian husband would be seen only by his wife. Since only one person could be in seeing range, only one person could strike the blow and only one person could be the murderer. Or murderess, rather. Agent Gruer, you will remember, said that only one person could have done it. Anyone else he considered impossible. Well?"

"He also said," said Baley, "that that one person couldn't have done it, either."

"By which he probably meant that there was no weapon found at the scene of the crime. Presumably Mrs. Delmarre could explain that anomaly."

He gestured with cool robotic politeness toward where Gladia sat, still in viewing focus, her eyes cast down, her small mouth compressed.

Jehoshaphat, thought Baley, we're forgetting the lady.

Perhaps it was annoyance that had caused him to forget. It was Daneel who annoyed him, he thought, with his unemotional approach to problems. Or perhaps it was himself, with his emotional approach. He did not stop to analyze the matter.

He said, "That will be all for now, Gladia. However one goes about it, break contact. Good-by."

She said softly, "Sometimes one says, 'Done viewing,' but I like 'Good-by' better. You seem disturbed, Elijah. I'm sorry, because I'm used to having people think I did it, so you don't need to feel disturbed."

Daneel said, "Did you do it, Gladia?"

"No," she said angrily.

"Good-by, then."

With the anger not yet washed out of her face she was gone. For a moment, though, Baley could still feel the impact of those quite extraordinary gray eyes.

She might say she was used to having people think her a murderess, but that was very obviously a lie. Her anger spoke more truly than her words. Baley wondered of how many other lies she was capable.

And now Baley found himself alone with Daneel. He said, "All right, Daneel, I'm not altogether a fool."

"I have never thought you were, Partner Elijah."

"Then tell me what made you say there was no murder weapon found at the site of the crime? There was nothing in the evidence so far, nothing in anything I've heard that would lead us to that conclusion."

"You are correct. I have additional information not yet available to you."

"I was sure of that. What kind?"

"Agent Gruer said he would send a copy of the report of their own investigation. I have that copy. It arrived this morning."

"Why haven't you shown it to me?"

"I felt that it would perhaps be more fruitful for you to conduct your investigation, at least in the initial stages, according to your own ideas, without being prejudiced by the conclusions of other people who, self-admittedly, have reached no satisfactory conclusion. It was because I, myself, felt my logical processes might be influenced by those conclusions that I contributed nothing to the discussion."

Logical processes! Unbidden, there leaped into Baley's mind the fragment of a conversation he had once had with a roboticist. A robot, the man had said, is logical but not reasonable.

He said, "You entered the discussion at the end."

"So I did, Partner Elijah, but only because by that time I had independent evidence bearing out Agent Gruer's suspicions."

"What kind of independent evidence?"

"That which could be deduced from Mrs. Delmarre's own behavior."

"Let's be specific, Daneel."

"Consider that if the lady were guilty and were attempting to prove herself innocent, it would be useful to her to have the detective in the case believe her innocent."

"Well?"

"If she could warp his judgment by playing upon a weakness of his, she might do so, might she not?"

"Strictly hypothetical."

"Not at all," was the calm reply. "You will have noticed, I think, that she concentrated her attention entirely on you."

"I was doing the talking," said Baley.

"Her attention was on you from the start; even before she could guess that you would be doing the talking. In fact, one might have thought she would, logically, have expected that I, as an Auroran, would take the lead in the investigation. Yet she concentrated on you."

"And what do you deduce from this?"

"That it was upon you, Partner Elijah, that she pinned her hopes. You were the Earthman."

"What of that?"

"She had studied Earth. She implied that more than once. She knew what I was talking about when I asked her to blank out the outer daylight at the very start of the interview. She did not act surprised or uncomprehending, as she would most certainly have done had she not had actual knowledge of conditions on Earth."

"Well?"

"Since she has studied Earth, it is quite reasonable to suppose that she discovered one weakness Earthmen possess. She must know of the nudity tabu, and of how such a display must impress an Earthman."

"She - she explained about viewing - "

"So she did. Yet did it seem entirely convincing to you? Twice she allowed herself to be seen in what you would consider a state of improper clothing - "

"Your conclusion," said Baley, "is that she was trying to seduce me. Is that it?"

"Seduce you away from your professional impersonality. So it would seem to me. And though I cannot share human reactions to stimuli, I would judge, from what has been imprinted on my instruction circuits, that the lady meets any reasonable standard of physical attractiveness. From your behavior, moreover, it seems to me that you were aware of that and that you approved her appearance. I would even judge that Mrs. Delmarre acted rightly in thinking her mode of behavior would predispose you in her favor."

"Look," said Baley uncomfortably, "regardless of what effect she might have had on me, I am still an officer of the law in full possession of my sense of professional ethics. Get that straight. Now let's see the report."

Baley read through the report in silence. He finished, turned back, and read it through a second time.

"This brings in a new item," he said. "The robot."

Daneel Olivaw nodded.

Baley said thoughtfully, "She didn't mention it."

Daneel said, "You asked the wrong question. You asked if he was alone when she found the body. You asked if anyone else had been present at the death scene. A robot isn't 'anybody else."

Baley nodded. If he himself were a suspect and were asked who else had been at the scene of a crime, he would scarcely have replied: "No one but this table."

He said, "I suppose I should have asked if any robots were present?" (Damn it, what questions does one ask anyway on a strange world?) He said, "How legal is robotic evidence, Daneel?"

"What do you mean?"

"Can a robot bear witness on Solaria? Can it give evidence?"

"Why should you doubt it?"

"A robot isn't human, Daneel. On Earth, it cannot be a legal witness."

"And yet a footprint can, Partner Elijah, although that is much

less a human than a robot is. The position of your planet in this respect is illogical. On Solaria, robotic evidence, when competent, is admissible."

Baley did not argue the point. He rested his chin on the knuckles of one hand and went over this matter of the robot in his mind.

In the extremity of terror Gladia Delmarre, standing over her husband's body, had summoned robots. By the time they came she was unconscious.

The robots reported having found her there together with the dead body. And something else was present as well; a robot. That robot had not been summoned; it was already there. It was not one of the regular staff. No other robot had seen it before or knew its function or assignment.

Nor could anything be discovered from the robot in question. It was not in working order. When found, its motions were disorganized and so, apparently, was the functioning of its positronic brain. It could give none of the proper responses, either verbal or mechanical, and after exhaustive investigation by a robotics expert it was declared a total loss.

Its only activity that had any trace of organization was its constant repetition of "You're going to kill me - you're going to kill me - you're going to kill me."

No weapon that could possibly have been used to crush the dead man's skull was located.

Baley said suddenly, "I'm going to eat, Daneel, and then we see Agent Gruer again - or view him, anyway."

Hannis Gruer was still eating when contact was established. He ate slowly, choosing each mouthful carefully from a variety of dishes, peering at each anxiously as though searching for some hidden combination he would find most satisfactory.

Baley thought: He may be a couple of centuries old. Eating may be getting dull for him.

Gruer said, "I greet you, gentlemen. You received our report, I believe." His bald head glistened, as he leaned across the table to reach a titbit.

"Yes. We have spent an interesting session with Mrs. Delmarre also," said Baley.

"Good, good," said Gruer. "And to what conclusion, if any, did you come?"

Baley said, "That she is innocent, sir."

Gruer looked up sharply. "Really?"

Baley nodded.

Gruer said, "And yet she was the only one who could see him, the only one who could possibly be within reach... ."

Baley said, "That's been made clear to me, and no matter how firm social customs are on Solaria, the point is not conclusive. May I explain?"

Gruer had returned to his dinner. "Of course."

"Murder rests on three legs," said Baley, "each equally important. They are motive, means, and opportunity. For a good case against any suspect, each of the three must be satisfied. Now I grant you that Mrs. Delmarre had the opportunity. As for the motive, I've heard of none."

Gruer shrugged. "We know of none." For a moment his eyes drifted to the silent Daneel.

"All right. The suspect has no known motive, but perhaps she's a pathological killer. We can let the matter ride for a while, and continue. She is in his laboratory with him and there's some reason why she wants to kill him. She waves some club or other heavy object threateningly. It takes him a while to realize that his wife really intends to hurt him. He shouts in dismay, 'You're going to kill me,' and so she does. He turns to run as the blow descends and it crushes the back of his head. Did a doctor examine the body, by the way?"

"Yes and no. The robots called a doctor to attend Mrs. Delmarre and, as a matter of course, he looked at the dead body, too."

"That wasn't mentioned in the report."

"It was scarcely pertinent. The man was dead. In fact, by the time the doctor could view the body, it had been stripped, washed, and prepared for cremation in the usual manner."

"In other words, the robots had destroyed evidence," said Baley, annoyed. Then: "Did you say he viewed the body? He didn't see it?"

"Great Space," said Gruer, "what a morbid notion. He viewed it, of course, from all necessary angles and at close focus, I'm sure. Doctors can't avoid seeing patients under some conditions, but I can't conceive of any reason why they should have to see corpses. Medicine is a dirty job, but even doctors draw the line somewhere."

"Well, the point is this. Did the doctor report anything about the nature of the wound that killed Dr. Delmarre?"

"I see what you're driving at.' You think that perhaps the wound was too severe to have been caused by a woman."

"A woman is weaker than a man, sir. And Mrs. Delmarre is a small woman."

"But quite athletic, Plainclothesman. Given a weapon of the proper type, gravity and leverage would do most of the work. Even not allowing for that, a woman in frenzy can do surprising things."

Baley shrugged. "You speak of a weapon. Where is it?"

Gruer shifted position. He held out his hand toward an empty glass and a robot entered the viewing field and filled it with a colorless fluid that might have been water.

Gruer held the filled glass momentarily, then put it down as though he had changed his mind about drinking. He said, "As is stated in the report, we have not been able to locate it."

"I know the report says that. I want to make absolutely certain of a few things. The weapon was searched for?"

"Thoroughly."

"By yourself?"

"By robots, but under my own viewing supervision at all times. We could locate nothing that might have been the weapon."

"That weakens the case against Mrs. Delmarre, doesn't it?"

"It does," said Gruer calmly. "It is one of several things about the case we don't understand. It is one reason why we have not acted against Mrs. Delmarre. It is one reason why I told you that the guilty party could not have committed the crime, either. Perhaps I should say that she apparently could not have committed the crime."

"Apparently?"

"She must have disposed of the weapon someway. So far, we have lacked the ingenuity to find it."

Baley said dourly, "Have you considered all possibilities?"

"I think so."

"I wonder. Let's see. A weapon has been used to crush a man's skull and it is not found at the scene of the crime. The only alternative is that it has been carried away. It could not have been carried away by Rikaine Delmarre. He was dead. Could it have been carried away by Gladia Delmarre?"

"It must have been," said Gruer.

"How? When the robots arrived, she was on the floor unconscious. Or she may have been feigning unconsciousness, but anyway she was there. How long a time between the murder and the arrival of the first robot?"

"That depends upon the exact time of the murder, which we don't know," said Gruer uneasily.

"I read the report, sir. One robot reported hearing a disturbance and a cry it identified as Dr. Delmarre's. It was apparently the closest to the scene. The summoning signal flashed five minutes afterward. It would take the robot less than a minute to appear on the scene." (Baley remembered his own experiences with the rapid-fire appearance of robots when summoned.) "In five minutes, even ten, how far could Mrs. Delmarre have carried a weapon and returned in time to assume unconsciousness?"

"She might have destroyed it in a disposer unit."

"The disposer unit was investigated, according to the report, and the residual gamma-ray activity, was quite low. Nothing sizable had been destroyed in it for twenty-four hours."

"I know that," said Gruer. "I simply present it as an example of what might have been done."

"True," said Baley, "but there may be a very simple explanation. I suppose the robots belonging to the Delmarre household have been checked and all were accounted for."

"Oh yes."

"And all in reasonable working order?"

"Yes."

"Could any of those have carried away the weapon, perhaps without being aware of what it was?"

"Not one of them had removed anything from the scene of the crime. Or touched anything, for that matter."

"That's not so. They certainly removed the body and prepared it for cremation."

"Well, yes, of course, but that scarcely counts. You would expect them to do that."

"Jehoshaphat!" muttered Baley. He had to struggle to keep calm.

He said, "Now suppose someone else had been on the scene."

"Impossible," said Gruer. "How could someone invade Dr. Delmarre's personal presence?

"Suppose!" cried Baley. "Now there was never any thought in the

robots' minds that an intruder might have been present. I don't suppose any of them made an immediate search of the grounds about the house. It wasn't mentioned in the report."

"There was no search till we looked for the weapon, but that was a considerable time afterward."

"Nor any search for signs of a ground-car or an air vehicle on the grounds?"

"No."

"Then if someone had nerved himself to invade Dr. Delmarre's personal presence, as you put it, he could have killed him and then walked away leisurely. No one would have stopped him or even seen him. Afterward, he could rely on everyone being sure no one could have been there."

"And no one could," said Gruer positively.

Baley said, "One more thing. Just one more. There was a robot involved. A robot was at the scene."

Daneel interposed for the first time. "The robot was not at the scene. Had it been there, the crime would not have been committed."

Baley turned his head sharply. And Cruer, ,who had lifted his glass a second time as though about to drink, put it down again to stare at Daneel.

"Is that not so?" asked Daneel.

"Quite so," said Gruer. "A robot would have stopped one person from harming another. First Law."

"All right," said Baley. "Granted. But it must have been close. It was on the scene when the other robots arrived. Say it was in the next room. The murderer is advancing on Delmarre and Delmarre cries out, 'You're going to kill me.' The robots of the household did not hear those words; at most they heard a cry, so, unsummoned, they did not come. But this particular robot heard the words and First Law made it come unsummoned. It was too late. Probably, it actually saw the murder committed."

"It must have seen the last stages of the murder," agreed Gruer. "That is what disordered it. Witnessing harm to a human without having prevented it is a violation of the First Law and, depending upon circumstances, more or less damage to the positronic brain is induced. In this case, it was a great deal of damage."

Gruer stared at his fingertips as he turned the glass of liquid to and fro, to and fro.

Baley said, "Then the robot was a witness. Was it questioned?"

"What use? He was disordered. It could only say 'You're going to kill me.' I agree with your reconstruction that far. They were probably Delmarre's last words burned into the robot's consciousness when everything else was destroyed."

"But I'm told Solaria specializes in robots. Was there no way in which the robot could be repaired? No way in which its circuits could be patched?"

"None," said Gruer sharply.

"And where is the robot, now?"

"Scrapped," said Gruer.

Baley raised his eyebrows. "This is a rather peculiar case. No motive, no means, no witnesses, no evidence. Where there was some evidence to begin with, it was destroyed. You have only one suspect and everyone seems convinced of her guilt; at least, everyone is certain no one else can be guilty.' That's your opinion, too, obviously. The question then is: Why was I sent for?"

Gruer frowned. "You seem upset, Mr. Baley." He turned abruptly to Daneel. "Mr. Olivaw."

"Yes, Agent Gruer."

"Won't you please go through the dwelling and make sure all windows are closed and blanked out? Plainclothesman Baley may be feeling the effects of open space."

The statement astonished Baley. It was his impulse to deny Gruer's assumption and order Daneel to keep his place when, on the brink, he caught something of panic in Gruer's voice, something of glittering appeal in his eyes.

He sat back and let Daneel leave the room.

It was as though a mask had dropped from Gruer's face, leaving it naked and afraid. Gruer said, "That was easier than I had thought. I'd planned so many ways of getting you alone. I never thought the Auroran would leave at a simple request, and yet I could think of nothing else to do."

Baley said, "Well, I'm alone now."

Gruer said, "I couldn't speak freely in his presence. He's an Auroran and he is here because he was forced on us as the price of having you." The Solarian leaned forward. "There's something more

to this than murder. I am not concerned only with the matter of who did it. There are parties on Solaria, secret organizations... ."

Baley stared. "Surely, I can't help you there."

"Of course you can. Now understand this: Dr. Delmarre was a Traditionalist. He believed in the old ways, the good ways. But there are new forces among us, forces for change, and Delmarre has been silenced."

"By Mrs. Delmarre?"

"Hers must have been the hand. That doesn't matter. There is an organization behind her and that is the important matter."

"Are you sure? Do you have evidence?"

"Vague evidence, only. I can't help that. Rikaine Delmarre was on the track of something. He assured me his evidence was good, and I believe him. I knew him well enough to know him as neither fool nor child. Unfortunately, he told me very little. Naturally, he wanted to complete his investigation before laying the matter completely open to the authorities. He must have gotten close to completion, too, or they wouldn't have dared the risk of having him openly slaughtered by violence. One thing Delmarre told me, though. The whole human race is in danger."

Baley felt himself shaken. For a moment it was as though he were listening to Minnim again, but on an even larger scale. Was everyone going to turn to him with cosmic dangers?

"Why do you think I can help?" he asked.

"Because you're an Earthman," said Gruer. "Do you understand? We on Solaria have no experience with these things. In a way, we don't understand people. There are too few of us here."

He looked uneasy. "I don't like to say this, Mr. Baley. My colleagues laugh at me and some grow angry, but it is a definite feeling I have. It seems to me that you Earthmen must understand people far better than we do, just by living among such crowds of them. And a detective more than anyone. Isn't that so?"

Baley half nodded and held his tongue.

Gruer said, "In a way, this murder was fortunate. I have not dared speak to the others about Delmarre's investigation, since I wasn't sure who might be involved in the conspiracy, and Delmarre himself was not ready to give any details till his investigation was complete. And even if Delmarre had completed his work, how would we deal with the matter afterward? How does one deal with hostile human

beings? I don't know. From the beginning, I felt we needed an Earthman. When I heard of your work in connection with the murder in Spacetown on Earth, I knew we needed you. I got in touch with Aurora, with whose men you had worked most closely, and through them approached the Earth government. Yet my own colleagues could not be persuaded into agreeing to this. Then came the murder and that was enough of a shock to give me the agreement I needed. At the moment, they would have agreed to anything."

Gruer hesitated, then added, "It's not easy to ask an Earthman to help, but I must do so. Remember, whatever it is, the human race is in danger. Earth, too."

Earth was doubly in danger, then. There was no mistaking the desperate sincerity in Gruer's voice.

But then, if the murder were so fortunate a pretext for allowing Gruer to do what he so desperately wanted to do all the time, was it entirely fortune? It opened new avenues of thought that were not reflected in Baley's face, eyes, or voice.

Baley said, "I have been sent here, sir, to help. I will do so to the best of my ability."

Gruer finally lifted his long-delayed drink and looked over the rim of the glass at Baley. "Good," he said. "Not a word to the Auroran, please. Whatever this is about, Aurora may be involved. Certainly they took an unusually intense interest in the case. For instance, they insisted on including Mr. Olivaw as your partner. Aurora is powerful; we had to agree. They say they include Mr. Olivaw only because he worked with you before, but it may well be that they wish a reliable man of their own on the scene, eh?"

He sipped slowly, his eyes on Baley.

Baley passed the knuckles of one hand against his long cheek, rubbing it thoughtfully. "Now if that - "

He didn't finish, but leaped from his chair and almost hurled himself toward the other, before remembering it was only an image he was facing.

For Gruer, staring wildly at his drink, clutched his throat, whispering hoarsely, "Burning... burning..."

The glass fell from his hand, its contents spilling. And Gruer dropped with it, his face distorted with pain.