I dragged my bag inside, threw the lever that closed the entry behind me. A green light went on. I walked along the narrow passage, lined with gray metal shelves stacked with gray steel tape drums, descended steps, came into a larger chamber fitted out with bunks, a tiny galley, toilet facilities, shelves stocked with food. There was a radio, a telephone and a second telephone, bright red. That would be the hot-line to Washington. This was the sanctum sanctorum, where the last survivors could wait out the final holocaust-indefinitely.

I opened the door of a steel cabinet. Radiation suits, tools, instruments. Another held bedding. I found a tape-player, tapes-even a shelf of books. I found a first aid kit and gratefully gave myself a hypo-spray jolt of neurite. My pains receded.

I went on to the next room; there were wash tubs, a garbage disposal unit, a drier. There was everything here I needed to keep me alive and even comfortable until I could convince someone up above that I shouldn't be shot on sight.

A heavy door barred the way to the room beyond. I turned a wheel, swung the door back, saw more walls lined with filing cabinets, a blank faзade of gray steel; and in the center of the room, alone on a squat table-a yellow plastic case that any Sunday Supplement reader would have recognized.

It was the Master Tape, the Utter Top Secret Programming document that would direct the terrestrial defense in case of a Gool invasion.

It was almost shocking to see it lying there-unprotected except for the flimsy case. The information it contained in micro-micro dot form could put my world in the palm of the enemy's hand.

The room with the tool kit would be the best place to work, I decided. I brought the suitcase containing the electronic gear back from the outer door where I'd left it, opened it and arranged its contents on the table. According to the Gool these simple components were all I needed. The trick was in knowing how to put them together.

There was work ahead of me now. There were the coils to wind, the intricate antenna arrays to lay out; but before I started, I'd take time to call Kayle-or whoever I could get at the other end of the hot-line. They'd be a little startled when I turned up at the heart of the defenses they were trying to shield.

I picked up the receiver and a voice spoke:

"Well, Granthan. So you finally made it."

6

"Here are your instructions," Kayle was saying. "Open the vault door. Come out-stripped-and go to the center of the parking lot. Stand there with your hands over your head. A single helicopter manned by a volunteer will approach and drop a gas canister. It won't be lethal, I promise you that. Once you're unconscious, I'll personally see to it that you're transported to the Institute in safety. Every effort will then be made to overcome the Gool conditioning. If we're successful, you'll be awakened. If not…"

He let the sentence hang. It didn't need to be finished. I understood what he meant.

I was listening. I was still not too worried. Here I was safe against anything until the food ran out-and that wouldn't be for months.

"You're bluffing, Kayle," I said. "You're trying to put the best face on something that you can't control. If you'd-"

"You were careless at Delta Labs, Granthan. There were too many people with odd blanks in their memories and too many unusual occurrences, all on the same day. You tipped your hand. Once we knew what we were up against, it was simply a matter of following you at an adequate distance. We have certain shielding materials, as you know. We tried them all. There's a new one that's quite effective.

"But as I was saying, we've kept you under constant surveillance. When we saw which way you were heading, we just stayed out of sight and let you trap yourself."

"You're lying. Why would you want me here?"

"That's very simple," Kayle said harshly. "It's the finest trap ever built by man-and you're safely in it."

"Safely is right. I have everything I need here. And that brings me to my reason for being here-in case you're curious. I'm going to build a matter transmitter. And to prove my good faith, I'll transmit the Master Tape to you. I'll show you that I could have stolen the damned thing if I'd wanted to."

"Indeed? Tell me, Granthan, do you really think we'd be fools enough to leave the Master Tape behind when we evacuated the area?"

"I don't know about that-but it's here."

"Sorry," Kayle said. "You're deluding yourself." His voice was suddenly softer, some of the triumph gone from it. "Don't bother struggling, Granthan. The finest brains in the country have combined to place you where you are. You haven't a chance, except to do as I say. Make it easy on yourself. I have no wish to extend your ordeal."

"You can't touch me, Kayle. This vault is proof against a hell-bomb, and it's stocked for a siege…"

"That's right," Kayle said. "It's proof against a hell-bomb. But what if the hell-bomb's in the vault with you?"

I felt like a demolition man, working to defuse a blockbuster, who's suddenly heard a loud click! from the detonator. I dropped the phone, stared around the room. I saw nothing that could be a bomb. I ran to the next room, the one beyond. Nothing. I went back to the phone, grabbed it up.

"You ought to know better than to bluff now, Kayle!" I yelled. "I wouldn't leave this post now for half a dozen hypothetical hell-bombs!"

"In the center room," Kayle said. "Lift the cover over the floor drain. You'll find it there. You know what they look like. Don't tamper with its mechanism; it's internally trapped. You'll have to take my word for it we didn't bother installing a dummy."

I dropped the phone, hurried to the spot Kayle had described. The bomb casing was there-a dully gray ovoid, with a lifting eye set in the top. It didn't look dangerous. It just lay there quietly, waiting…

Back at the telephone, I had trouble finding my voice. "How long?" I croaked.

"It was triggered when you entered the vault," Kayle said. "There's a time mechanism. It's irreversible; you can't force anyone to cancel it. And it's no use your hiding in the outer passages.

"The whole center will be destroyed in the blast. Even it can't stand against a bomb buried in its heart. But we'll gladly sacrifice the center to eliminate you."

"How long!"

"I suggest you come out quickly, so that a crew can enter the vault to disarm the bomb."

"How long!"

"When you're ready to emerge, call me." The line went dead.

I put the phone back in its cradle carefully, like a rare and valuable egg.

I tried to think. I'd been charging full speed ahead ever since I had decided on my scheme of action while I was still riding the surf off the Florida coast, and I'd stuck to it. Now it had hatched in my face-and the thing that had crawled out wasn't the downy little chick of success. It had teeth and claws and was eyeing me like a basilisk.

But I still had unplayed aces-if there was time.

I had meant to use the matter transmitter to stage a dramatic proof that I wasn't the tool of the enemy. The demonstration would be more dramatic than I'd planned. The bomb would fit the machine as easily as the tape. The wheels would be surprised when their firecracker went off-right on schedule-in the middle of the Mojave Desert.

I set to work, my heart pounding. If I could bring this off-if I had time-if the transmitter worked as advertised…

The stolen knowledge flowed smoothly, effortlessly. It was as though I had been assembling matter transmitters for years, knew every step by heart. First the moebius windings; yard after yard of heavy copper around a core of carbon; then the power supply, the first and second stage amplimitters…