The Watcher was a labyrinth. It wasn’t easy to get in, even with the external sensors covered by the thirsty algae. They had to burn it away from the hull to find a way in.

After they had forced an entrance at a bulky lock, the party of twelve found themselves floating through winding spaghetti corridors. Some necked down to scarcely a hand’s width. Others swelled until an elephant could have wallowed through.

A strange humming fled through the lacquered walls Skittering tones shot through the electromagnetic spectrum. Nigel followed Carlos down a tube that seemed to drop away into infinity. Red panels spattered random glows on bulk-heads and complex equipment. Nigel tried to see a pattern to the illumination, but most of it seemed to be wasted on bare, plain metal and stone.

The Watcher was half an asteroid, just as the ancient Icarus craft had been. Into the carbon and raw metal of a minor planet something had fitted elaborate technology. And whatever ran the Watcher lurked somewhere here. Nigel drew Nikka close and followed Carlos. The silence of the place hung like a warning.

They did not have to wait long.

Things long and snakelike scuttled from holes. Bigger machines, tubular and awkward, jetted down side corridors.

There were impossibly many of them. The humans fired at the approaching machines with a grim desperation. Laser bolts and e-beam cutters lanced forth.

They were almost surprised to see their shots fall sure and hard on the machines. Parts blew away. Electrical arcs flared blue-white, then died. The machines tumbled forward, out of control, and smashed into walls.

There are so many! Carlos called. He had a laser projector in each hand and two power packs strapped to him.

Turn sideways, so you’ll be a smaller target, Nikka answered.

Down this way, Nigel called.

They fled the hordes. Nigel rebounded from three walls in quick succession and darted down a narrow tube. Weightlessness gave him back the deft reflexes he had too long missed. As soon as Carlos and Nikka had caught up to him he turned down a side passage. Two slender machines, glossy with glazed ceramic, came at him. He punctured each with a bolt of tightly bound electrons.

Carlos began, What are—

Nigel sent a signal back into the passage they had left. Crimson light burst upon them. A crackling of electromagnetic death ricocheted through their comm lines.

“Implosion devices I cooked up,” Nigel said. “Spits out electromagnetic noise. I’ve been dropping them every hundred meters.”

Nikka said, I see. It will burn out these creatures?

“Hope so.”

It did. The swarms who staffed the Watcher had once been made to defend it against intrusion. But time works its way even with stolid machines. Those which wore out were replaced, but each time the basic instructions were engraved into fresh silicon or ferrite memory, a small probability existed of a mistake. The weight of these errors accumulated, like autumn leaves blown into a chance pocket of a backyard, making improbably dense piles.

So the minions of the Watcher had devolved. They were slow, sluggish, and dumb in just the deadly crafts of battle that life could never afford to neglect. Humanity’s penchant for warfare now paid off.

It took hours to work their way through the Watcher. Small machines launched themselves at any moving figure. Some exploded suicidally. Others jumped from ambush. Mines detonated, ripping at legs and lungs.

Nigel played cat and mouse down the dark corridors. He used stealth and tricks and, to his own vast surprise, stayed alive.

More men and women launched from the base on Pocks. They slipped aboard like pirates and joined battle.

In the end the machines retreated. Running, they were even less able. They were blown apart or fried with microwave bursts. Every machine fought to the very end. It was obvious that whatever had designed the Watcher had not thought deeply about the chance that it would be boarded. After all, the vast ship was intended to bombard planets, perhaps even kindle suns to a quickening fire. Hand-to-hand fighting was not its style.

Still, over half of the humanity that entered the Watcher left as corpses. Many more groaned and sweated with deep wounds. Others bit their lips at the pain and swore with ragged, angry pride. The last machines they found, cowering now in dim hiding holes, they smashed with great relish into small, twisted fragments.

Much of the Watcher labyrinth they would never understand. It was a forest of glazed surfaces, nested cables, inexplicable tangles of technology alien to all humanity’s avenues of thought.

But they did understand the small ship they found.

It was buried near the center of the vast complex. It had a curious blue-white sheen, as if the metal were fired in some unimaginably hot furnace. Yet it opened easily at a touch of a control panel.

Carlos said, “It’s not the same design as the rest of this Watcher. Looks finer, I’d say. The Watcher is solid but crude. This thing …”

Nigel nodded, The craft was a hundred meters long, but still seemed tiny and precious compared with the monstrous Watcher. And its arabesqued surfaces, its feeling of lightness and swift grace, conveyed its function.

“It’s a fast ship,” Nikka observed, passing a hand over circuits that leapt into amber life.

“I agree,” Nigel said. “The Watcher’s a blunderbuss. This is a stiletto. Or maybe an arrow.”

Carlos touched the hard, dimly alabaster-lit surfaces of it. They stood in what had to be a control room. Screens blossomed into unintelligible displays when they approached. “Robots flew it, I guess,” Carlos said. “Must’ve built the Watcher around this.”

“Perhaps.” Nigel calculated. They had already found evidence that the Watcher was very old, perhaps as much as a billion years. Radioactive isotope dating techniques were fairly accurate, even for such long durations. If this ship was older, it implied a machine civilization of vast age.

“I wonder if we could use it? Figure out the controls?” Nigel wondered.

Carlos brightened. “Sail it to Earth? My God! Yes!”

“Earth?” Nigel hadn’t thought of that.

They were all intensely aware that they were like fishermen swallowed by a whale.

Somewhere in the huge Watcher was the guiding intelligence. Its minions destroyed, it had withdrawn. But it would not give up.

Eventually it would find a way to strike back at the vermin which had invaded it. The Watcher had time. It could move subtly, deliberately.

The corridors took on a brooding, watchful cast.

No one went anywhere alone.

It took three days to find the core.

A crewman led Nigel to the small, compact room near the geometric center of the Watcher’s huge mass.

“Looks like an art gallery, I’d wager,” Nigel said after a long moment of surveying the curved walls.

It was a wilderness of tangled curves. Nothing sat flush with the walls. Small, ornate surfaces butted against each other, each rippling with embedded detail. Patterns swam, merged, oozed. A giddy sense of flight swept over Nigel as he watched the endless slide of structure move through the room.

“This is where it thinks?” he asked.

A crewman said at his elbow. “Maybe. Functions seem to lead into here.”

“What’s that?” A hole gaped, showing raw splintered struts.

“Defense mechanism. Killed Roselyn when she came in. I got it with a scrambler.”

Nigel noticed that some of the panels were spattered with drying brown flecks. The Watcher was exacting a price for each of its secrets.

He sighed and pointed. “And that?”

The crewman shrugged.

A pattern came and went, as though it was a huge ocean wreck seen deep beneath the shifting waves.

It was first a line, then an ellipse, and now a circle. Its surface piped and worked with tenuous detail. Somehow the walls seemed to contain it as an embedded image, persistent against the passing shower of lesser facts. Nigel frowned. An unsettling, alien way to display information. If that’s what it was.