In a vault below the vaults of his largest villa, Marcus Licinius Crassus looked on at his crowd of gold. The room burned with nearly a hundred torches, but it was still hard to make out every statue's face. There were slaves, and freedmen, and some who he'd even recognised. What had struck these people had done it indiscriminately, like the most barbarian disease.

He was the greatest of Rome's most powerful men. But it had still been a challenge to steal and buy his way to owning every statue person in the city. He'd had assistance, though, of a very unusual kind. The richest people in Rome had slaves for the smallest things. But no man other than Crassus had one entirely devoted to mysteries.

It wasn't long since he had first bought Thresu, when his last slave of mysteries fell to the thing with the hands of a man. He'd shown the young man a few of the things that should never have been in the world, but this was the first time he'd face something that Crassus considered a threat.

"Gold," he said to the slave. "It's worth what it is because it doesn't decay, and because there's never very much of it. I've spent so much on getting a little gold; I don't want someone to go around making more. Every person who changes," he snarled, "makes me a much poorer man."

"They're really people, then?" said Thresu, still stunned despite his position.

"Not anymore," said Crassus, "and I fear they're of less value to me."

Thresu looked at the frozen faces of men, women and children, each seeming unbothered by the fact they were made of metal.

"It's funny," he said, "how their eyes seem to follow you around the room."

"That's because their eyes are following you around the room," said his master. "And soon their bodies will, too, and their fists. They're not human, not anymore. But sometimes they still get a little animated ."

Thresu looked worriedly at the nearest figure; a soldier armed with a sword of gold. As he watched the snarl on its face grew fiercer, and he nervously drew his dagger to his hand.

"A good test, isn't it?" said Crassus, "for a new slave of the mysteries." He twisted a brooch on his toga, and smiled as anachronistic armour wrapped around his form.

"You said I'd be a scholar," Thresu protested uselessly, "not a gladiator!"

"You'll need to be both," said his master from behind a visor, "if you're going to last very long in this role."

The entire room of statues was moving now; faces and bodies wrapped in confusion and pain. But through his life Thresu had learned some level of cunning, and the value of having no honour in a fight. He grabbed a torch from the curved wall and thrust it to the hand of the golden soldier, moving it with the wrist as it curled and writhed. Even heated, no Roman steel could cut through solid gold, but Thresu's blade was different: given to him in secret by his master, and carved from the tooth of a monster that had no name. That beast had chewed through diamonds in a place beyond, and it sliced the hand clean from its owner now. If the statue felt pain, it showed no sign of it: it just bought its remaining hand open to crush closed Thresu's throat.

Thresu has meant to slice through the statue with its spear, but in his fear he'd been thinking of it as flesh. As he tried to thrust the weapon through his foe it glanced against the gold, and he saw with horror that the other statues were now moving towards him too. He thrust his dagger out in a desperate spiral, knowing there was no way he could fend off the entire room—

—and then suddenly there was a rush of air, and the movement of something too fast to see. Flashes of a sword far sharper than a soldier's seemed to swipe through the nearest statues, then to sear through ones that lurked much further away. Before Thresu had any idea what was happening the room stood still, with the golden people cut down to shapeless lumps.

"Of course you couldn't beat them," said his master. "I have something greater than you for that." He nodded to the figure beside them both, who had cut all the golden figures down.

Thresu had once seen an old marble statue, with all the paint that had covered it stripped clean. Its stone had reminded him of bloodless flesh, somehow kept living beyond its death. The thing before him now was like that statue, but he knew that it was alive, examining him through lidless eyes of stone.

"It's a monster," he said.

"He once was a man just like you," said Crassus. "A soldier, and he's a soldier still. It's not men who he fights anymore, but he does protect the city, even if he does it as part of protecting me. I call him The Rex."

Thresu had absorbed enough of his captor's culture to be shocked by that.

"But that means—"

Crassus laughed. "Tell me, Thresu. If there are no kings in Rome. What better name than the name of a king, to fight what we pretend isn't here?"

That sounded like the kind of question to which any answer would result in a beating, and so Thresu kept as expressionless as he could.

"You are high for a slave," said Crassus. "And I do trust you with this. Command the Rex. Take him where the thing in his sack guides you, to end the source of this endless gold. Do this, and you'll be worthy of more mysteries. And maybe even freedom, one of these days."

"Yes," said Thresu. "I'll be a guide to your king."

"He's not my king," said Crassus. "He's my slave. Never forget that. It doesn't matter if you're a free man, or if you're turned to marble. You're still mine in this city, as long as I'm still alive. And as long as the thing that makes the gold," he snarled, "becomes very dead indeed."

"Your guide," Crassus continued as he opened the Rex's sack.

"He sees me as what I'm made of," said a voice in Thresu's mind, " Like if you were a piece of meat. But I'm worth much more than what I appear to be. Even if I was built all out of gold."

A thing shaped like a leech floated out of the sack, wings all down each side flapping gently as it went. It was complex and luminous in a way only living things could be, but even so it was clear that it wasn't made out of flesh.

"Salt," said the voice. "A voice made of it, beyond time itself. And we'll have an interesting time together, as I already know."

"Is," said Thresu to his master. "Um. I don't wish to be impudent. But is that creature also—"

"Talking to me?" said Crassus. "Oh, probably. But I stopped listening a long time ago. It's pretentious and it sees the future; that's a very bad combination. Gold and swords, they're how I make my predictions. They're usually about how I'm going to win."

Thresu bowed, and the man like stone did as well.

"Watch him," said Crassus. "Watch, and guard, and wait for the kill."

Thresu nodded, and went as fast from the room as couldn't be mistaken for rudeness.

"I hope he succeeds," said Crassus to his endless lumps of gold. "So many dead slaves of mysteries. Someone might start to think I have a problem."

None of the metal that had been men responded as it lay on the ground. It stayed there dead as gold should be, and not even the flicker of the torchlight could convince someone it had once been alive.