“Certainly not!” S’greela’s head jerked a couple of feet higher, dislodging several hundred Tinker components. “That was already agreed.”

“So we have no choice, we have to find a way to lure the Simmie out from Dreamsea. Angel, you’ve been giving me nothing but negatives. What does interest or alarm it?”

“We do not know. If you suggest alternatives, we can test them against the thought-process model. But so far we have found nothing that provides a strong stimulant, either positive or negative.”

“Hmmm.” Shikari was stirring now, aroused by S’greela’s sudden movement. The Tinker was close to maximum size. “Hmmm.”

The others waited. They were used to Shikari’s long integration time when all the components were clustered.

“We feel stupid to suggest this,” said the Tinker at last. “But we know how the Simmie chooses to spend most of its time. It watches the sun, the moon, the planets, and the stars. One of its interests must be astronomy. Would it possibly be willing to move for some extraordinary sight of them?”

Chan felt they were clutching at straws. But it was something to have the others at least participate. He turned to the immobile hulk of the Angel. “Can you run that?”

“We are already doing so. A few moments more.” A twenty second silence was broken only by the clucking of Angel’s communicator. Chan had learned to associate those chirps and clicks with massive computation within the Singer’s crystalline matrix. “Shikari’s hypothesis can be sustained,” said Angel at last. “The Simulacrum is certainly an observer of celestial events. At a 0.88 probability level, it would move for a sight of something unprecedented in its astronomical experience. We have discovered no other stimulus that has better than 0.35 correlation with the observed Simulacrum movements.” There was a shorter silence, ended by a wiggle of Angel’s lower fronds and a very human-sounding sigh from its computer communicator. “Unfortunately, this conclusion appears to be of theoretical value only. We have checked the ephemeris relevant to Barchan. No sidereal events of an unusual nature can be expected for another half year.”

Chan nodded.

“You do not seem surprised, or dispirited,” said Shikari. “Perhaps you have it in mind to pray for a supernova?”

“Not quite. I find that prayers don’t work when you need them most. Unless you answer them for yourself.” While the others stared at him, Chan turned to S’greela. “You understand the mechanics of the aircar better than any of us. Can it be made to hover with no one on board, under automatic control and at a pre-determined height?”

“Certainly. That is trivial.”

“And could it be made to move with the stars, so that to an observer on the surface of Barchan it would appear to be far beyond the atmosphere?”

“Probably.” A speculative buzz came from the Pipe-Rilla. “With careful programming of the onboard control computer to refer movement to a sidereal reference frame, I think it can be done.”

“And it could be shielded, or illuminated from within, in such a way that it would appear as a natural stellar or planetary phenomenon in the observing wavelengths employed by the Simmie?”

“Possibly. For that, I must consult Angel.” S’greela was staring at Chan questioningly. “But to what avail, all this effort?”

“As a lure. We already know the terrain around the Simmie habitat, thanks to Shikari’s component flights. That gives us the topography, too, which tells us what will be visible from a particular location. If we were to plan for movement of the aircar, over several nights, so that a continued view of it would call for a particular ground path to be followed, leading away from the shore of Dreamsea — ”

“ — a difficult problem of inverse computation,” said Angel. “Given the terrain, to define an aircar movement that would lead the Simulacrum to follow a prescribed path, one that ensures continued ground visibility.”

“Difficult, maybe. But exactly the sort of thing that you know how to do, Angel. We tease the Simmie away from its hiding-place, away from Dreamsea. Then once it’s well away from all the Shellback habitats, we can go in and we can — we can subdue it.”

Subdue. Chan knew better than to say the words that were really in his mind. Kill. Destroy. Annihilate. Murder. Those were the right words, and all uniquely human.

It was not a fact likely to make any human feel proud.

Chan’s “plan” was so simple-minded and fallible that he had hesitated even to suggest it. The instant acceptance by all the others gave him a new insight into the members of the Stellar Group. Even Angel, with its great intellect, found certain thought patterns quite inaccessible. If humanity’s worst fear ever came true and an aggressive species appeared from beyond the Perimeter, then defense would have to rely on humans alone. Intelligent as they were, the others would be no more than cannon fodder. It was no criticism of them; they simply could not think in the necessary terms.

But in every other area that Chan could imagine, the alien members of the team functioned outstandingly. S’greela and Shikari had done an unbelievable job on the aircar. Hovering under automatic control, high above Barchan, the car seemed a brilliant celestial phenomenon, a comet that streamed its tail (How had the two of them ever managed that effect?) halfway across the night sky. Every evening the apparition shone brighter and more colorful. But every evening, moving like a true cometary orbit, its appearance became visible farther to the north. A good view of it from the shores of Dreamsea became more and more difficult.

Angel had calculated the Simulacrum’s most probable path away from the side of the lake. Chan had examined that path on foot, and decided the best ambush point and the best position for each team member. Angel, too slow to be any use physically during the final moments of confrontation, had been assigned the role of observer. It would occupy an oversight position, and warn the others if and when the Simmie left its hiding-place under the shelf of rock. The form of that warning had been the subject of heated argument until Chan cut off the discussion. He was worried by the Simmie’s intelligence and the sophistication of its sensing apparatus. He had vetoed any signal that might be intercepted and decoded. If the Simmie moved from its hideout, Angel would transmit a single flash of light, tightly beamed towards the others.

S’greela worried that the signal might be missed, until the Tinker offered a reassurance: with the many thousands of eyes available in Shikari’s composite, some would always be focused on Angel’s secluded position.

And the time for action was finally arriving. Shikari whistled softly in the warm night air. Angel Had given the sign, and the Simmie Artefact was on the way. The positions of the other three had been chosen carefully. If the Simmie followed anywhere close to the path predicted by Angel, each of them would have a clear shot at it without endangering the others. And no matter what variation on the path the Simmie might adopt, if it followed the aircar at all two of the team would have a good target.

Chan, Shikari, and S’greela were sitting roughly ninety degrees apart on the perimeter of a circle which had the Simmie’s most probable emergence point at its center. If and when it appeared they would be less than thirty meters away from it.

Chan glanced at his watch. Any time now, according to Angel s prediction. He froze, and tried not to blink his eyes.

It was there. The latticed wing panels of the Simmie, peeping into view above a sharp edge of rock. Ten more seconds, and the silver-blue body would be revealed. At this range it would be impossible to miss. Already Chan had his weapon lined up in the correct firing position.

He had a last-minute worry. Would S’greela and Shikari have had the sense to prepare their weapons ahead of time? Any warning noise now could ruin everything.