I squatted, chewing on a glucose tab.

L’Eesh called, “You know, there’s something odd here. I thought this was a fort, or perhaps some equivalent of a cathedral. But it looks for all the world as if it crashed here.”

“You don’t make aircraft from brick.”

“Well, whatever made such a vast, ungainly structure fly through the air is gone now. Nevertheless there was clearly once a pretty advanced civilization here. On the way in I glimpsed extensive ruins. And some of those impact craters looked deliberately placed. This whole world is an arena of war. But it seems to have been a war that was fought with interplanetary weapons, and then flying brick fortresses, and at last, fire and clubs … ”

He laughed, fiddling with his hood. “Of course it’s likely both moons were inhabited. Life could have been sparked on either moon, in some tidal puddle stirred by the Jovian parent. And then panspermia would work, spores wafting on meteorite winds, two worlds developing in parallel, cross-fertilizing … ”

On he talked. I wasn’t interested. I was here for Ghosts, not archaeology.

I waited until he took the lead, and we walked on, leaving the ruined township behind.

Another “night,” another broken sleep in the dirt. Another “day” on that endless plain.

We didn’t seem to get any closer to that damn bridge. In places the surface had been blasted to glass; it prickled my feet as I staggered across it.

We had nothing to do but talk.

A lot of it was L’Eesh’s refined bragging. “You know, I always wondered why the Commission is so tolerant of us, we hunters. Under the Druz Coalition, you aren’t supposed to get old and rich. The species is the thing! It is not comfortable to feel one has been manipulated, controlled. But it has been glorious nevertheless.”

Turned out L’Eesh had taken part in that great Ghost massacre on Snowball.

“Snowball was actually the first Ghost planet anybody found. When Ghost numbers collapsed the Commission slapped on conservation orders—some nonsense about preserving cultural diversity—but there wasn’t a great deal of will behind the policing.

“When the orders were lifted, we were already in orbit. We made a huge circle around the major Ghost nest, with aerial patrols overhead, and we just worked our way in on foot, firing at will, until we met in the center. The major challenge was counting up the carcasses.

“So it went: while those nests lasted, it was a feeding frenzy. You were born too late, Raida.”

“After all of that, why go on? Why risk your neck in places like this, for the last few scraps of hide?”

“Because some day there will be a last Ghost of all. I must be there when he is brought down. You know, a thousand years ago the Ghosts’ pits of twisted spacetime struck dread into human hearts. They were deployed as fortresses, a great wall right across the disc of the Galaxy. Magnificent! … And now we hunt the Ghosts for their hides.”

“Who cares? Ghosts are predators.”

“They are symbiotes,” he said gently. “You have been listening to too much Commission propaganda.”

As we talked we walked on, across a land like a dusty table-top.

L’Eesh kept up his dogged, unspectacular plod, hour after hour. He looked determined, sharp, as if he had plenty of reserve.

I was determined not to let my own gathering weakness show. I continued to carry that bone spear.

At the end of the third “day,” we reached the bridge.

L’Eesh was breathing hard, sucking water. “Magnificent,” he said. “Mad. They built a brick tower to reach to heaven! … ”

Exhausted, filthy, uncomprehending, I peered up. About a hundred paces across, it was just a rough pile of mud bricks. And yet it towered above me, reaching up to infinity.

I went exploring.

I came to a crumbled gap in the base of the tower. I crawled into an unlit interior. My suit’s low-output bioluminescent lamp glowed.

I craned my neck. The bridge rose up vertically above me, a tunnel into the sky. Metal gleamed amid the rubble on the floor.

I kicked aside half-bricks and uncovered a squat cuboid about half my height. It was featureless except for a fat red button. When I pressed the button, the cube rose magically into the air, trailing a rose-colored sparkle, like the bogeys’ weapon; I kept out of the way of the wake. When I released the button, the cube dropped again.

It was pretty obviously a lifting palette.

There was another palette buried in the wall of the bridge—and further up another, and another beyond that.

“Now we know how they made their castles fly,” L’Eesh said. “And how they raised this bridge.” He was standing beside me, his suit glowing green. I saw he had scraped a channel in mold-softened brick with his thumb. Beneath it, something gleamed, copper-brown. “It’s not metal,” he said. “Not even like Xeelee construction material.”

“Maybe that’s the original structure.”

“Yes. No suite of moons is stable enough to allow the building of a brick bridge between them; the slightest tidal deflection would be enough to bring it tumbling down. There must be something more advanced here—perhaps the moons’ orbits are themselves regulated somehow … The bridge itself is just a clumsy shell. The inhabitants must have constructed it after the intervention.”

“What intervention?”

He sighed. “Think, child. Try to understand what you see around you. Imagine millennia of war between the two moons—”

“What was there to fight over?”

“That scarcely ever matters. Perhaps it was just that these were sibling worlds. What rivalry is stronger? Finally, the moons were ruined, serving only as a backdrop for the unending battles—until peacemakers sent down blood-red rays, vacuum energy beams that turned the weapons to dust.”

“Peacemakers? Silver Ghosts?”

“Well, it’s possible,” he said. “Though it’s not characteristic of Ghost behavior. It was a draconian solution: a quarantine of technology, the trashing of two spacefaring civilizations … How arrogant. Almost human.”

I felt uncomfortable discussing Ghosts with human-like motives. “What about these lift palettes?”

“It makes a certain sense,” he said. “From the point of view of a meddling Ghost, anyhow. A simple technology to help the survivors to rebuild their ruined worlds—something you surely couldn’t turn into a weapon—but it didn’t work out.” He smiled thinly. “Instead the populations used the gifts to build this insane bridge.”

“How is this going to help us find the Ghosts?”

He seemed surprised by the question. “There are no Ghosts here, child.”

… Of course, he was right. Ghosts spread out over every world they infest. We would have seen them by now, if they were here. I’d known this, I guess, but I hadn’t wanted to face the possibility that I’d thrown away my life for nothing.

I slumped to the littered floor. The strength seemed to drain out of me.

In retrospect, I can see his tactics. It was as if he had designed the whole situation, a vast trap. He waited until I had reached the bottom—at the maximum point of my tiredness, as I was crushed with disappointment at the failure of the hunt, surrounded by alien madness.

Then he struck.

The length of bone came looming out of the dark, without warning, straight at my head.

I ducked. The bone clattered against the wall. “L’Eesh—”

“It’s just business, child.”

My heart hammered. I backed away until my spine was pressed against the rough wall. “You’ve found something you want. The vacuum-energy weapons. Is that it?”

“Not what we came for, but I’ll turn a profit, if I can manage to get off of this moon.”

“It’s not as if you need to do this,” I said bitterly.

He nodded. “You have the stronger motive here. Which is why I have to destroy you.” He spoke patiently, as if instructing a child. He raised the bone, its bulging end thick, hefting it like a club, and he moved toward me, his movements oily, powerful.