"I'm Amati, the supratendent. Why?" The scowl was heavy.

Karnes couldn't take any chances. The man might be perfectly okay, but—

Lansberg's steps sounded, coming up the stairs. With him was a Manhattan Squad officer of the Police Department.

"Shhh, Mr. Amati. C'mere a minute," said the cop.

"Oh. Lootenant Carnotti. Whatsa—"

"Shhhhhh! C'mere, I said, and be quiet!"

"You know this man?" Lansberg asked the policeman softly, indicating Amati.

"Sure. He's okay."

Lansberg turned to the superintendent. "What do you know about the guy who just came in?"

Amati seemed to have realized that something serious was going on, for his voice dropped to a conspiratorial whisper. "I dunno. I don't-a see who it is. Whatsa goin' on, Lootenant Carnotti?"

"What about Apartment 523? Who lives there?" asked Karnes.

"Oh, them? Meester and Meeses Seigert. Artists. Sheesa paint pictures, heesa make statues." Then Amati's eyes widened knowingly. "Ohhh! You guys da Vice Squad, eh? I theenk theresa someteeng fonny about them!"

Footsteps sounded coming down the stairs from above.

"We watched the indicator needle on the elevator door in the lobby, and I signalled the 'copters on the roof," Lansberg whispered.

The hallway began to fill quietly with police.

Lieutenant Carnotti assigned one of the men to watch Amati, mainly in order to keep him out of the way, and Karnes led the men down the hall towards 523, guns drawn.

Karnes knocked boldly on the door.

"Yeah? Who is it?" asked someone inside.

Karnes pitched his voice a little lower than normal, and said: "It's-a me, Meester Amati, only me, the soopratendant."

The imitation wasn't perfect, but the muffling effect of the door would offset any imperfections.

"Oh, sure, Mr. Amati. Just a sec." There was a short pause, filled with muffled conversation, then somebody was unlocking the door.

Things began to happen fast. As the door came open, Karnes saw that it had one of those inside chain locks on it that permit the door to be opened only a few inches. Without hesitation, he threw his weight against the door. Lansberg was right behind him.

Under the combined weight of the two men, the chain ripped out of the woodwork, permitting the door to swing free. As it did so, it slammed into the face of the man who had opened it, knocking him backwards.

There were seven or eight other men and two women in the room. One of the men already had a heavy pistol out and was aiming it at the doorway. Karnes dropped to the floor and fired just as the other's pistol went off.

The high-velocity three millimeter slug whined through the air above Karnes' head and buried itself in Lansberg's shoulder. Lansberg dropped, spun halfway around from the shock. His knees hit Karnes in the back.

Karnes lurched forward a little, and regained his balance. Something flew out of his coat pocket and skittered across the floor. Karnes didn't notice what it was until one of the men across the room picked it up.

Brittain had picked up the mind impressor!

Karnes was aware that there were more men behind him firing at another of the conspirators who had made the mistake of drawing a weapon, but he wasn't interested too much. He was watching Brittain.

It only took seconds, but to Karnes it seemed like long minutes. Brittain had evidently thought the impressor was a weapon when he picked it up, and, after seeing his mistake, had started to throw it at the door. Then the impressor shimmered slightly, as though there were a hot radiator between the observor and the object. Brittain stopped, paralyzed, his eyes widening.

Then he gasped and threw the impressor against the floor as hard as he could.

"NO!" he screamed, "IT'S A LIE!"

The impressor struck the floor and broke. From its shattered interior came a blinding multi-colored glare. Then there was darkness. Karnes fainted.

When Karnes awoke, one of the policemen was shaking him.

"Wake up, Mr. Karnes, wake up!"

Karnes sat up abruptly. "What happened?" He had no time to be original.

"I don't know for sure. One of the Leaguers threw a gas bomb of some sort, and it knocked out everyone in the room. Funny, though, it even knocked out all the Leaguers. When the rest of the boys came in, everybody was out cold on the floor. Most of them are coming out of it now, except for two of the Leaguers. They got some lead in them, though, not gas."

Karnes stood up. He felt a little dizzy, but otherwise there wasn't anything wrong. He surveyed the room.

On the floor was a slightly yellowed spot where the impressor had flared and vanished. Lansberg was unconscious with a copiously bleeding right shoulder. Two other men were rapidly being brought around by the police. Three of the League agents were still out; nobody tried to wake them up, they were being handcuffed.

One of the women was crying and cursing the "damned filthy Nations police" over one of the bodies, and the other woman was sitting stonily, staring at her handcuffs with a faint sneer.

"Where's Brittain?" roared Karnes. The man was nowhere in the room.

"Gone," said one of the cops. "Evidently he skipped out while the rest of us were unconscious. He was the guy who threw the bomb."

Karnes glanced at his watch. One sixteen in the morning. They had been out about twelve or thirteen minutes.

"Where the devil did he go? How in—"

Lieutenant Carnotti came up to him, a look of self-disgust on his face. "I know how he got away, Mr. Karnes; I just talked to the boys on the roof. He grabbed a uniform coat and cap off Sergeant Joseph while he was out and commandeered a 'copter on the roof."

Karnes didn't wait for further information. He ran out into the hall and into the open elevator. Within less than a minute, he was on the roof.

One cop was speaking rapidly into a transmitter.

"—number 3765. Left about ten minutes ago, supposedly for the hospital. Officer Powers in the 'copter with him."

He cut off and looked at Karnes, who was standing over him. His gun was out before he spoke. "Who are you, buddy."

Karnes told him who he was. The cop looked skeptical. Karnes didn't have his hat on, and his clothes were a bit rumpled after his nap on the floor.

Karnes didn't need to say anything; another policeman was going through his pockets, and he found the billfold. As soon as they saw the forgeproof identity card, they relaxed.

"Sorry, Mr. Karnes," said the man at the transceiver, "but we've already let one man get away."

Karnes nodded. "I know. Pure blind luck that his suit was almost the same shade as that gray uniform you guys wear, or he'd never have got away with it. All he needed was the jacket and cap."

"Have any idea which way he went?"

The cop shrugged. "He came up here and told us that three men had been shot down below and some more gassed. He said Mr. Lansberg had sent him for a hospital call. Then he jumped in a 'copter with Powers and headed northeast. We didn't pay much attention. After all, he was wearing a sergeant's stripes."

Northeast. That would be toward Long Island. But, naturally, he would circle; he wouldn't be dumb enough to head in the right direction until he was out of sight. Or would he?

"Get on that radio again," he told the radioman, "—and tell them I want that man alive. Get that—alive!"

"Right." The officer switched on his microphone and began to talk.

Karnes pinched the bridge of his nose and closed his eyes in an attempt to concentrate. With Lansberg shot up, that put the Brittain case in his hands. Theoretically, he should be pumping the prisoners down below to find out how much higher the spy ring went.

But his real interest lay in Brittain, himself. There was no doubt that he had received another message from the impressor before he had thrown it