On the least lonely and best defended of all human worlds, not even the past was safe from enemy invasion.
It had the shape of a man, the brain of an electronic devil.
It and the machines like it were the best imitations of men and women that the berserkers, murderous machines themselves, were able to devise and build. Still, they could be seen as obvious frauds when closely inspected by any humans.
"Only twenty-nine accounted for?" the supervisor of Defense demanded sharply. Strapped into his combat chair, he was gazing intently through the semitransparent information screen before him, into space. The nearby bulk of Earth was armored in the dun-brown of defensive force fields, the normal colors of land and water and air invisible.
"Only twenty-nine." The answer arrived on the flagship's bridge and a sharp sputtering of electrical noise. The tortured voice continued. "And it's quite certain now that there were thirty to begin with."
"Then where's the other one?"
There was no reply.
All of Earth's defensive forces were still on full alert, though the attack had been tiny, no more than an attempt at infiltration, and seemed to have been thoroughly repelled.
A small blur leaped over Earth's dun-brown limb, hurtling along on a course that would bring it within a few hundred kilometers of the supervisor's craft. This was Power Station One, a tamed black hole. In time of peace the power-hungry billions on the planet drew from it half their needed energy. Station One was visible to the eye only as a slight, flowing distortion of the stars beyond.
Another report was coming in. "We are searching space for the missing berserker android, Supervisor."
"You had damned well better be."
"The infiltrating enemy craft had padded containers for thirty androids, as shown by computer analysis of its debris. We must assume that all containers were filled."
Life and death were in the supervisor's tones. "Is there any possibility that the missing unit got past you to the surface?"
"Negative, Supervisor." There was a slight pause. "At least we know it did not reach the surface in our time."
"Our time? What does that mean, babbler? How could . . . ah."
The black hole flashed by. Not really tamed, though that was a reassuring word, and humans applied it frequently. Just harnessed, more or less.
Suppose—and, given the location of the skirmish, the supposition was not unlikely—that berserker android number thirty had been propelled, by some accident of combat, directly at Station One. It could easily have entered the black hole. According to the latest theories, it might conceivably have survived to reemerge intact into the universe, projected out of the hole as its own tangible image in a burst of virtual-particle radiation.
Theory dictated that in such a case the re-emergence must take place before the falling in. The supervisor crisply issued orders. At once his computers on the world below, the Earth Defense Conglomerate, took up the problem, giving it highest priority. What could one berserker android do to Earth? Probably not much. But to the supervisor, and to those who worked for him, defense was a sacred task. The temple of Earth's safety had been horribly profaned.
To produce the first answers took the machines eleven minutes.
"Number thirty did go into the black hole sir. Neither we nor the enemy could very well have foreseen such a result, but—"
"What is the probability that the android emerged intact?"
"Because of the peculiar angle at which it entered, approximately sixty-nine percent."
"That high!"
"And there is a forty-nine-percent chance that it will reach the surface of the earth in functional condition, at some point in our past. However, the computers offer reassurance. As the enemy device must have been programmed for some subtle attack upon our present society, it is not likely to be able to do much damage at the time and place where it—"
"Your skull contains a vacuum of a truly intergalactic order. I will tell you and the computers when it has become possible for us to feel even the slightest degree of reassurance. Meanwhile, get me more figures."
The next word from the ground came twenty minutes later.
"There is a ninety-two-percent chance that the landing of the android on the surface, if that occurred, was within one hundred kilometers of fifty-one degrees, eleven minutes north latitude; zero degrees, seven minutes west longitude."
"And the time?"
"Ninety-eight-percent probability of January 1, 1880 Christian Era, plus or minus ten standard years."
A landmass, a great clouded island, was presented to the supervisor on his screen.
"Recommended course of action?"
It took the ED Conglomerate an hour and a half to answer that.
The first two volunteers perished in attempted launchings before the method could be improved enough to offer a reasonable chance of survival. When the third man was ready, he was called in, just before launching, for a last private meeting with the supervisor.
The supervisor looked him up and down, taking in his outlandish dress, strange hairstyle, and all the rest. He did not ask whether the volunteer was ready but began bluntly: "It has now been confirmed that whether you win or lose back there, you will never be able to return to your own time."
"Yes, sir. I had assumed that would be the case."
"Very well." The supervisor consulted data spread before him. "We are still uncertain as to just how the enemy is armed. Something subtle, doubtless, suitable for a saboteur on the earth of our own time—in addition, of course, to the superhuman physical strength and speed you must expect to face. There are the scrambling or the switching mindbeams to be considered; either could damage any human society. There are the pattern bombs, designed to disable our defense computers by seeding them with random information. There are always possibilities of biological warfare. You have your disguised medical kit? Yes, I see. And of course there is always the chance of something new."
"Yes, sir." The volunteer looked as ready as anyone could. The supervisor went to him, opening his arms for a ritual farewell embrace.
He blinked away some London rain, pulled out his heavy ticking timepiece as if he were checking the hour, and stood on the pavement before the theater as if he were waiting for a friend. The instrument in his hand throbbed with a silent, extra vibration in addition to its ticking, and this special signal had now taken on a character that meant the enemy machine was very near to him. It was probably within a radius of fifty meters.
A poster on the front of the theater read:
"The real problem, sir," proclaimed one top-hatted man nearby, in conversation with another, "is not whether a machine can be made to win at chess, but whether it may possibly be made to play at all."
No, that is not the real problem, sir, the agent from the future thought. But count yourself fortunate that you can still believe it is.
He bought a ticket and went in, taking a seat. When a sizable audience had gathered, there was a short lecture by a short man in evening dress, who had something predatory about him and also something frightened, despite the glibness and the rehearsed humor of his talk.
At length the chess player itself appeared. It was a desklike box with a figure seated behind it, the whole assembly wheeled out on stage by assistants. The figure was that of a huge man in Turkish garb. Quite obviously a mannequin or a dummy of some kind, it bobbed slightly with the motion of the rolling desk, to which its chair was fixed. Now the agent could feel the excited vibration of his watch without even putting a hand into his pocket.
The predatory man cracked another joke, displayed a hideous smile, then, from among several chess players in the audience who raised their hands—the agent was not among them—he selected one to challenge the automaton. The challenger ascended to the stage, where the pieces were being set out on a board fastened to the rolling desk, and the doors in the front of the desk were being opened to show that there was nothing but machinery inside.
The agent noted that there were no candles on this desk, as there had been on that of Maelzel's chess player a few decades earlier. Maelzel's automaton had been an earlier fraud, of course. Candles had been placed on its box to mask the odor of burning wax from the candle needed by the man who was so cunningly hidden inside amid the dummy gears. The year in which the agent had arrived was still too early, he knew, for electric lights, at least the kind that would be handy for such a hidden human to use. Add the fact that this chess player's opponent was allowed to sit much closer than Maelzel's had ever been, and it became a pretty safe deduction that no human being was concealed inside the box and figure on this stage.
Therefore . . .
The agent might, if he stood up in the audience, get a clear shot at it right now. But should he aim at the figure or the box ? And he could not be sure how it was armed. And who would stop it if he tried and failed? Already it had learned enough to survive in nineteenth-century London. Probably it had already killed, to further its design—"under new management" indeed.
No, now that he had located his enemy, he must plan thoroughly and work patiently. Deep in thought, he left the theater amid the crowd at the conclusion of the performance and started on foot back to the rooms that he had just begun to share on Baker Street. A minor difficulty at his launching into the black hole had cost him some equipment, including most of his counterfeit money. There had not been time as yet for his adopted profession to bring him much income; so he was for the time being in straitened financial circumstances.
He must plan. Suppose, now, that he were to approach the frightened little man in evening dress. By now that one ought to have begun to understand what kind of a tiger he was riding. The agent might approach him in the guise of—
A sudden tap-tapping began in the agent's watch pocket. It was a signal quite distinct from any previously generated by his fake watch. It meant that the enemy had managed to detect his detector; it was in fact locked onto it and tracking.
Sweat mingled with the drizzle on the agent's face as he began to run. It must have discovered him in the theater, though probably it could not then single him out in the crowd. Avoiding horse-drawn cabs, four-wheelers, and an omnibus, he turned out of Oxford Street to Baker Street and slowed to a fast walk for the short distance remaining. He could not throw away the telltale watch, for he would be unable to track the enemy without it. But neither did he dare retain it on his person.
As the agent burst into the sitting room, his roommate looked up, with his usual, somewhat shallow, smile, from a leisurely job of taking books out of a crate and putting them on shelves.
"I say," the agent began, in mingled relief and urgency, "something rather important has come up, and I find there are two errands I must undertake at once. Might I impose one of them on you?"
The agent's own brisk errand took him no farther than just across the street. There, in the doorway of Camden House, he shrank back, trying to breathe silently. He had not moved when, three minutes later, there approached from the direction of Oxford Street a tall figure that the agent suspected was not human, its hat was pulled down, and the lower portion of its face was muffled in bandages. Across the street it paused, seemed to consult a pocket watch of its own, then turned to ring the bell. Had the agent been absolutely sure it was his quarry, he would have shot it in the back. But without his watch, he would have to get closer to be absolutely sure.
After a moment's questioning from the landlady, the figure was admitted. The agent waited for two minutes. Then he drew a deep breath, gathered up his courage, and went after it.
The thing standing alone at a window turned to face him as he entered the sitting room, and now he was sure of what it was. The eyes above the bandaged lower face were not the Turk's eyes, but they were not human, either.
The white swathing muffled its gruff voice. "You are the doctor?"
"Ah, it is my fellow lodger that you want." The agent threw a careless glance toward the desk where he had locked up the watch, the desk on some papers bearing his roommate's name were scattered. "He is out at the moment, as you see, but we can expect him presently. I take it you are a patient."
The thing said, in its wrong voice, "I have been referred to him. It seems the doctor and I share a certain common background. Therefore the good landlady has let me wait in here. I trust my presence is no inconvenience."
"Not in the least. Pray take a seat, Mr.—?"
What name the berserker might have given, the agent never learned. The bell sounded below, suspending conversation. He heard the servant girl answering the door, and a moment later his roommate's brisk feet on the stairs. The death machine took a small object from its pocket and sidestepped a little to get a clear view past the agent toward the door.
Turning his back upon the enemy, as if with the casual purpose of greeting the man about to enter, the agent casually drew from his own pocket a quite functional briar pipe, which was designed to serve another function, too. Then he turned his head and fired the pipe at the berserker from under his own left armpit.
For a human being he was uncannily fast, and for a berserker the android was meanly slow and clumsy, being designed primarily for imitation, not dueling. Their weapons triggered at the same instant.
Explosions racked and destroyed the enemy, blasts shatteringly powerful but compactly limited in space, self-damping and almost silent.
The agent was hit, too. Staggering, he knew with his last clear thought just what weapon the enemy had carried—the switching mindbeam. Then for a moment he could no longer think at all. He was dimly aware of being down on one knee and of his fellow lodger, who had just entered, standing stunned a step inside the door.
At last the agent could move again, and he shakily pocketed his pipe. The ruined body of the enemy was almost vaporized already. It must have been built to self-destruct when damaged badly, so that humanity might never learn its secrets. Already it was no more than a puddle of heavy mist, warping in slow tendrils out the slightly open window to mingle with the fog.
The man still standing near the door had put out a hand to steady himself against the wall. "The jeweler . . . did not have your watch," he muttered dazedly.
I have won, thought the agent dully. It was a joyless thought because with it came slow realization of the price of his success. Three quarters of his intellect, at least, was gone, the superior pattern of his brain-cell connections scattered. No. Not scattered. The switching mindbeam would have reimposed the pattern of his neurons somewhere farther down its pathway . . . there, behind those gray eyes with their newly penetrating gaze.
"Obviously, sending me out for your watch was a ruse." His roommate's voice was suddenly crisper, more assured than it had been. "Also, I perceive that your desk has just been broken into, by someone who thought it mine." The tone softened somewhat. "Come, man, I bear you no ill will. Your secret, if honorable, shall be safe. But it is plain that you are not what you have represented yourself to be."
The agent got to his feet, pulling at his sandy hair, trying desperately to think. "How—how do you know?"
"Elementary!" the tall man snapped.