The day was over. The crowd had dispersed. The city had taken on a quiet, almost sleepy atmosphere, with only an occasional knot of two or three still discussing the events of the past several hours.

And Bigman was annoyed.

With Morriss he had left the scene of the recent danger and zoomed out to Council headquarters. There Morriss had had his conference with Lucky, a conference to which Bigman was not allowed entry and from which the Venusian had emerged looking grimly angry. Lucky remained calm but uncommunicative.

Even when they were alone again, Lucky said merely, "Let's get back to the hotel. I need sleep, and so do you after your own little game today."

He hummed the Council March under his breath, as he always did when he was completely abstracted, and signaled a passing tollcar. The car stopped automatically when the sight of his outstretched hand with fingers spread wide registered on its photoelectric scanners.

Lucky pushed Bigman in before him. He turned the dials to indicate the co-ordinate position of the Hotel Bellevue-Aphrodite, put in the proper combination of coins, and let the machine's computer take over. With Ms foot he adjusted the speed lever to low.

The tollcar drifted forward with a pleasantly smooth motion. Bigman would have found it both comforting and restful if he had been in a less itchingly curious state of mind.

The little Martian flicked a glance at his large friend. Lucky seemed interested only in rest and thought. At least he leaned back on the upholstery and closed his eyes, letting the motion rock him while the hotel seemed to approach and then become a large mouth, which swallowed them as the tollcar automatically found the entrance to the receiving dock of the hotel's garage.

Only when they were in their own room did Bigman reach the point of explosion. He cried, "Lucky, what's it all about? I'm going nuts trying to figure it out."

Lucky stripped off his shirt and said, "Actually, it's only a matter of logic. What kind of accidents occurred as a result of men's being mentally dominated before today? What kind did Morriss mention? A man giving away money. A man dropping a bale of weed. A man placing poison in a nutrient mixture for yeast. In each case, the action was a small one, but it was an action. It was something done."

"Well?" said Bigman.

"All right, what did we have today? It wasn't something small at all; it was something big. But it wasn't action. It was exactly the opposite of action: A man put his hand on a dome-lock lever and then did nothing. Nothing!"

Lucky vanished into the bathroom and Bigman could hear the needle shower and Lucky's muffled gasps under its invigorating jets. Bigman followed at last, muttering savagely under his breath.

"Hey," he yelled.

Lucky, his muscled body drying in churning puffs of warm air, said, "Don't you get it?"

"Space, Lucky, don't be mysterious, will you? You know I hate that."

"But there's nothing mysterious. The mentalists have changed their entire style, and there must be a reason.

Don't you see the reason for having a man sit at a dome-lock lever and do nothing?"

"I said I didn't."

"Well, what was accomplished by it?"

"Nothing."

"Nothing? Great galaxy! Nothing? They only get half the population of Aphrodite and practically every official' out to the threatened sector in double-speed time. They get me out there and you and Morriss. Most of the city was left bare, including Council headquarters. And I was such a lunk that it was only when Turner, the city's chief engineer, mentioned how easy it would be to get out of the city with the police force disrupted that it occurred to me what was happening."

"I still don't see it. So help me, Lucky, I'm going

"Hold it, boy," Lucky seized Bigman's threatening fists in one large palm. "Here it is: I got back to Council headquarters as fast as possible and found that Lou Evans had already gone."

"Where did they take him?"

"If you mean the Council, they didn't take him anywhere. He escaped. He knocked down a guard, seized a weapon, used his Council wrist-mark to get a subship and escaped to sea."

"Was that what they were really after?"

"Obviously. The threat to the city was strictly a feint. As soon as Evans was safely out into the ocean, the man at the lock was released from control and, naturally, he surrendered."

Bigman's mouth worked. "Sands of Mars! All that stuff in the ventilating duct was for nothing. I was fifty kinds of cobbered fool."

"No, Bigman, you weren't," said Lucky, gravely. "You did a good job, a terrific job, and the Council is going to hear about it."

The little Martian flushed, and for a moment pride left no room in him for anything else. Lucky took the opportunity to get into bed.

Then Bigman said, "Bat Lucky, that means...I mean, if Councilman Evans got away by a trick of the mentalists, then he's guilty, isn't he?"

"No," said Lucky vehemently," he isn't."

Bigman waited, but Lucky had nothing more to say on the subject and instinct told Bigman to let the matter die. It was only after he had burrowed into the cool plastex sheets, having undressed and washed in his turn, that he tried again.

"Lucky?"

"Yes, Bigman."

"What do we do next?"

"Go after Lou Evans."

"We do? What about Morriss?"

"I'm in charge of the project now. I had Chief Councilman Conway put that across all the way from Earth."

Bigman nodded in the darkness. That explained why he himself had not been able to attend the conference. Friend though he might be of Lucky Starr a dozen times over, he was not a member of the Council of Science. And, in a situation where Lucky would have to move in over a fellow councilman's head and call in the authority of Earth and central headquarters to back him, non-councilmen were strictly not wanted as witnesses.

But now the old lust for action was beginning to stir in him. It would be into an ocean now, the vastest, most alien ocean on the inner planets. He said excitedly, "How early do we leave?"

"As soon as the ship they're outfitting is ready. Only first we see Turner."

"The engineer? What for?"

"I have the records on the men involved in the various mentalist incidents in the city up to today, and I want to know about the man at the lock dome, too. Turner is the man who's likely to know most about him. But before we see Turner..."

"Yes?"

"Before that, you Martian peanut, we sleep. Now shut up."

Turner's dwelling place turned out to be a rather large apartment house that seemed suited for people high in the administrative scheme of things. Bigman whistled softly when they passed into the lobby, with its paneled walls and trimensional seascapes. Lucky led the way into a trundle and pressed Turner's apartment number.

The trundle lifted them five floors, then took to the horizontal, skittering along on directed force beams and stopping outside the back entrance to Turner's apartment. They stepped out, and the trundle went off with a whirr, disappearing behind a turn in the corridor.

Bigman watched it wonderingly. "Say, I never saw one of those before."

"It's a Venusian invention," said Lucky. "They're introducing them into new apartment houses on Earth now. You can't do anything about the old apartment houses, though, unless you redesign the building to give each apartment a special trundle-served entrance."

Lucky touched the indicator, which promptly turned red. The door opened, and a woman looked out at them. She was slight of build, young and quite pretty, with blue eyes and blond hair drawn softly backward and over her ears in the Venusian fashion.

"Mr. Starr?"

"That's right, Mrs. Turner," said Lucky. He hesitated a trifle over the title; she was almost too young to be a housewife.

But she smiled at them in friendly fashion. "Won't you come in? My husband's expecting you, but he hasn't had more than two hours' sleep and he's not quite..."

They stepped in, and the door closed behind them. '

Lucky said, "Sorry to have to trouble you so early, but it's an emergency, and I doubt that we'll bother Mr. Turner long."

"Oh, that's all right. I understand." She stepped fussily about the room, straightening objects that required no straightening.

Bigman looked about curiously. The apartment was completely feminine-colorful, frilly, almost fragile. Then, embarrassed to find his hostess's eyes upon him, he said clumsily, "It's a very nice place you have here, miss-uh-ma'am."

She dimpled and said, "Thank you. I don't think Lyman is very fond of the way I have it arranged, but he never objects, and I just love little doodads and whatnots. Don't you?"

Lucky spared Bigman the necessity of answering by saying, "Have you and Mr. Turner been living here very long?"

"Just since we got married. Less than a year. It's a darling apartment house, just about the nicest in Aphrodite. It's got completely independent utilities, its own coaster garage, a central communo. It even has chambers underneath. Imagine! Chambers! Not that anyone ever uses them. Even last night. At least I think no one did, but I can't say, because I just slept right-through all the excitement. Can you imagine? I didn't even hear about it till Lyman came home."

"Perhaps that was best," said Lucky. "You missed a fright."

"I missed excitement, you mean," she protested. "Everyone in the apartment was out in the thick of it, and I slept. Slept all through it. No one woke me. I think that was terrible."

"What was terrible?" came a new voice, and Lyman Turner stepped into the room. His hair was rumpled; there were creases on his homely face and sleep in his eyes. He had his precious computer under his arm and put it down under the chair when he sat down.

"My missing the excitement," said his young wife. "How are you, Lyman?"

"All right, considering. And never mind missing the excitement. I'm glad you did... Hello, Starr. Sorry to delay you."

"I've only been here a few moments," said Lucky.

Mrs. Turner flew to her husband and pecked quickly at his cheek. "I'd better leave you men alone now."

Turner patted his wife's shoulder, and his eyes followed her affectionately as she left. He said, "Well, gentlemen, sorry you find me as you do, but I've had a rough time of it in the last few hours."

"I quite realize that. What's the situation with the dome now?"

Turner rubbed his eyes. "We're doubling the men at each lock, and we're making the controls a little less self-contained. That rather reverses the engineering trend of the last century. We're running power lines to various spots in the city so that we can shut the power off from a distance just in case any such thing ever happens again. And, of course, we will strengthen the transite barriers shielding the different sections of the city... Does either of you smoke?"

"No," said Lucky, and Bigman shook his head.

Turner said, "Well, would you toss me a smoke from the dispenser, the thing that looks like a fish? That's right. It's one of my wife's notions. There's no holding her back when it comes to getting these ridiculous gadgets, but she enjoys it." He flushed a little. "I haven't been married long, and I still pamper her, I'm afraid."

Lucky looked curiously at the odd fish, carved out of a stonelike, green material, from whose mouth a lighted cigarette had appeared when he pressed its dorsal fin.

Turner seemed to relax as he smoked. His legs crossed, and one foot moved back and forth in slow rhythm over his computer case.

Lucky said, "Anything new on the man who started it all? The man at the lock?"

"He's under observation. A madman, obviously."

"Does he have a.record of mental imbalance?"

"Not at all. It was one of the things I checked into. As chief engineer, you know, the dome personnel are under me."

"I know. It's why I came here to you."

"Well, I wish I could help, but the man was just an ordinary employee. He's been on our rolls for some seven months and never gave any trouble before. In fact, he had an excellent record; quiet, unassuming, diligent."

"Only seven months?"

"That's right,"

"Is he an engineer?"

"He has a rating as engineer, but actually his work consisted largely of standing guard at the lock. After all, traffic passes in and out of the city. The lock must be opened and closed, bills of lading checked, records kept. There's a lot more to managing the dome than just engineering."

"Did he have any actual engineering experience?"

"Just an elementary college course. This was his first job. He's quite a young man."

Lucky nodded. He said casually, "I understand there have been a whole series of queer accidents in the city lately."

"Have there?" Turner's weary eyes stared at Lucky, and he shrugged. "I rarely get a chance to look at the news-etheric tapes."

The communo buzzed. Turner lifted it and held it to his ear for a moment. "It's for you, Starr."

Lucky nodded. "I left word I'd be here." He took the communo but did not bother to activate the screen or to raise the sound above the ear-contact stage. He said, "Starr at this end."

Then he put it down and stood up. "We'll be going now, Turner."

Turner rose, too. "All right. If I can help you in the future, call on'me any time."

"Thank you. Give our respects to your wife, will you?"

Outside the building Bigman said, "What's up?"

"Our ship is ready," said Lucky, flagging down a groundcar.

They got in, and again Bigman broke the silence. "Did you find out anything from Turner?"

"A thing or two," said Lucky curtly.

Bigman stirred uneasily and changed the subject. "I hope we find Evans."

"I hope so, too."

"Sands of Mars, he's in a spot. The more I think of it, the worse it seems. Guilty or not, it's rough having a request for removal on grounds of corruption sent in by a superior officer."

Lucky's head turned and he looked down at Bigman. "Morriss never sent any report on Evans to central headquarters. I thought you understood that from yesterday's conversation with him."

"He didn't?" said Bigman incredulously. "Then who did?"

"Great Galaxy!" said Lucky. "Surely it's obvious. Lou Evans sent that message himself, using Morriss's name."