lockers, the two small desk-and-chair combinations. There was no window in the room. Indeed, there was nothing about the room or corridor to prove that they were not twenty miles underground. Certainly the jitney ride had been no reassurance to the contrary.

The dim wall lights glowed on scrubbed, peeling paint, and the floor was covered with clean but well-worn plastic matting. Against one wall was a TV set. Between the beds a door led into a compact lavatory and shower. Glancing in, Jeff saw the lavatory was also connected with the adjoining room.

"It's no Grand Hotel," the Nasty Frenchman said sourly. "But it's clean and it's a bed. This corridor quarters your whole unit—the C unit. Other units are on other floors, up and down."

Jeff looked around the room gloomily. "Where can I eat?"

"The mess hall's four flights down. Take the escalator at the end of the hall. It closes in half an hour, so you'd better step on it. And if you're smart, you won't go wandering around. These boys in gray you see here and there don't like us very much." His face creased into a sardonic grin as he started for the door. "And you'd be smart to change before you come down. The faster people stop thinking you're new here, the happier you'll be." With that, he turned and disappeared down the hall.

Jeff gave a sigh, and prowled the room. One of the foot lockers held an amazing assortment of clean and dirty clothes. On the floor of it lay a large heap of dirty shirts and trousers, and nested squarely in the center of the pile was a heap of gold rings and wrist watches. Jeff blinked, not quite believing his eyes. He hadn't thought to ask about his room-mate, but apparently he had one who had not yet made his appearance.

Apparently everyone wore similar clothing. He found the other locker filled with clean shirts and dungarees. Swiftly he started to change, his mind racing. His body was sore all over and he felt a dry, hot feeling around his ears from lack of sleep. His arm ached miserably every time he moved it. If only he could sleep for a little while. But he knew there was no time to be wasted. In the mess hall there would still be people. Somewhere among them he would find the girl....

Carefully he considered the problem. The girl was the key. He had to find her, to make certain that Conroe was here. And he had to find her quickly, catch her unawares, before she had a chance to alibi or hide. Conroe would be hidden; he would never come into the open until he was sure that he had not been followed. He too must be taken unawares. Jeff had seen Conroe slip out of too many traps in the past. A blunder now could be the last. And if Conroe had time to plan, there would be many, many blunders.

A car buzzed down the hall as he stood in the room and stopped a little way from the door. There were voices, subdued, yet carrying a sharp note of frantic excitement. Jeff paused, listening to the combination of unfamiliar sounds: a grunt, a low curse, a rustle of whispered conversation, a low whistle. Then the door to the next room banged open and a rumble and squeak of wheels came to his ears.

"Jeez, what a job!"

"Yeah, looks bad. Did the doc see him?"

"He said he'd be down—"

"—gotta let it wear off before you can tell. This was the works, this time."

Jeff walked quietly to the door of the connecting lavatory, his nerves tingling. A new sound was apparent, an unearthly sound of labored, gurgling breathing. Jeff shivered. He had heard a sound like that only once before in his life: in a rocket during the Asian war, when a man had been struck in the throat with a chunk of shrapnel. Carefully, he pushed the door open an inch, peered through....

There were three men standing in the room, maneuvering a man—if it was a man—from the four-wheeled cart onto the bed. The man's head was covered to the shoulders with bandage. A patch of fresh blood showed near the temple, and a rubber tube emerged where the mouth should have been.

"Got him down? Better cover him closer. Restrainers—he may jump around. Doc said three weeks for shock to wear off, if he makes it through the night."

"Yeah—and this is the Big Cash for Tinker too. Harpo nearly beat him to the job, but Schiml had promised him—"

Jeff shuddered. This, then, was one of the Mercy Men, finished with a "job." The gurgling sound grew louder, measuring itself with the man's breathing—short, shallow, a measure of death. An experiment had been completed.

Jeff closed the door silently. His face in the mirror was pasty white and his hands were shaking. Here was the factor that had been plaguing him from the start, finally breaking through to the surface. The road he was traveling was a one-way road. He had to find Conroe and get off the road quickly, while he could. Because he dared not travel the road too far....

The air in the corridor seemed fresher as Jeff started for the escalator. It was almost two o'clock and he hurried, anxious to reach the mess hall before it closed. He consciously fought the picture of the man on the bed out of his mind. With effort he focused his attention once again on the girl. At the end of the corridor he stepped onto the creaky, down-going escalator.

If only he could check with Ted Bahr, make certain that the trail had really ended at the Hoffman Center, make sure that Conroe was not really somewhere outside, still hiding, still running. One thing seemed certain: if Conroe were really here, he too would be faced with the testing and classification; he too would be traveling the same grim road as Jeff himself. And as a newcomer, he too would be under suspicion and scrutiny.

Jeff stopped short on a landing. He was suddenly aware that he had lost count of the flights he had gone down. He looked back to check his bearings, then moved around to the stairs moving up. The escalator creaked and groaned, as if every turn would be its last, and Jeff stared dreamily at the moving wall, waiting—until he passed the open well to the opposite stairs.

He froze, his mind screaming. Unable to move, he stared at the pale, frightened face of the man on the down-going stairway. In the brief seconds while they passed, he stood rooted, paralyzed, unable to cry out. Then with a hoarse yell he turned. Half-stumbling, half-falling, he ran down the up-going stairs until he reached the opening.

Then he vaulted across the barrier, crashing his shoulder against the wall as he went through. He caught a glimpse of the tall, slender figure running from the bottom of the stairs into the corridor at the bottom, and he shouted again in a burst of blinding rage. He took the steps three at a time, his mind numb to the pain as his foot struck the solid floor and twisted, sending him sprawling on his face. In an instant he was on his feet again, running, frantically, blindly, to the end of the corridor.

It broke into two hallways, going off in a Y. Both were dark and both were empty. Jeff stood panting, almost screaming out in rage, his whole body trembling. He started blindly down one corridor, jerked open a door and stared in at the small, empty office. He tried another door and another. Then he turned and ran back to the Y, spun around the corner and ran pell-mell down the second corridor. Only his own desperate footfalls echoed back to him in the darkness.

Back at the Y, he sank to the floor. Still panting, he sobbed aloud in his rage, clenching his fists as he tried to regain control of his spinning mind. Rage there was—yes, and hatred and bitter frustration. But also, tumbling through his mind in a wild, elated cadence, was a cry of sheer, incoherent savage joy. Because he knew now, beyond any shadow of doubt, that Paul Conroe was among the Mercy Men.

He looked up suddenly at the two figures approaching him from the lighted corridor. One of them held a tiny, deadly scorcher pistol trained on his chest. The other, a huge, burly man, reached down and jerked Jeff's face up into the light. "What's your unit?" the