After a little more business the meeting wound up.

Brica approached her mother. Deep in her sixth pregnancy, she walked almost as cautiously as old Messalina, and she propped her hands on her back for support. Beside her, her eldest daughter Agrippina walked with eyes shyly downcast.

Regina smiled, and put her hand on Brica’s bulge. “I can feel her, or him,” Regina said. “Restless little soul.”

“She longs to be out in the world — as I long for her to be out, too.”

Brica truly did look exhausted. She was in her forties now, and this child, her third by her second husband, had proven especially trying. Besides, that new husband was not so supportive as dull but good- hearted Castor — who had eventually fallen in love with a woman from beyond the Order, and now lived in contentment with a young second family in a jostling suburb, safe from the subterranean strangeness of the Crypt. But still, Agrippina had proven a strong support as she had grown, as had Brica’s second daughter, eleven years old, named Julia for her long-dead great-grandmother.

It was Agrippina, as it happened, that Brica wanted to talk about.

“Her bleeding has begun,” Brica said softly, and Agrippina’s face purpled. “It is time for her celebration — the first of my children to become a woman.” Brica hugged her daughter. “Already the boys watch her — I’ve seen their eyes — and soon she will be having babies of her own.”

“Oh, Mother, ” muttered the wretched Agrippina.

“I’ll be a grandmother,” said Brica. “And you, Mother, a great -grandmother. With Agrippina fertile I won’t be having any more children of my own … I hope this will be the last before my change … As for the ceremony—”

“No,” said Regina sharply.

Agrippina looked at her in shock.

Brica said, “But every girl since Venus — on my own wedding day, as you remember well, Mother — has been celebrated.” Anger flared briefly. “What are you saying — that my daughter, your own blood, isn’t good enough for such an honor?”

“No, of course not.” Regina thought fast, but inconclusively. It had been another impulsive decision, whose basis she didn’t yet understand herself. “I didn’t mean that. Of course you must plan the ceremony,” she said, seeking time to think.

But she and Brica were of course long-established combatants, and Brica had caught that note of sharpness. She glared at her mother, but her face was a hollow-eyed mask of fatigue, and she clearly did not want to argue.

Brica took her daughter’s arm. “Fine. Come, Agrippina.” And they left the peristylium without looking back.

Since that dreadful day when the Vandals had ravaged Rome, things had changed greatly for the Order.

As the Order’s wealth had increased, a great deal had been invested in the estate on the Appian Way, which today served primarily as a school. But even more money had been sunk underground.

The use of the Catacombs had proven so obviously valuable that nobody had objected when Regina had suggested extending and modifying them. The old cemetery directly beneath the house remained, almost unmodified; for a Christian order it would have been disrespectful to have disturbed such a shrine. But the tunnels had been greatly extended, and new rooms and passageways had been dug into the soft rock.

After fifteen years of steady burrowing the Order’s underground warren, buried deep in the Roman ground, had spread over two levels. It housed three hundred people, almost all of them women and children. It was comfortable, once you got used to the dim light and cramped corridors. Of course the Crypt would always be dependent on the surface world, for an inflow of food and water, an outflow of sewage, and for money and building materials and labor: the complex could never cut adrift of the world, like a ship sailing away into an underground sea. But the Council had done all they could to maintain a wide range of links and relationships with suppliers and customers and allies in the outside world, making their sources as diverse as possible, so they were dependent on no one group or person.

As the depth of the Crypt had increased, incidences of flooding or collapse had been dealt with by brute force, with the application of plenty of Roman concrete and brick. Problems with ventilation and heating had been more insidious. Air shafts had been dug out, to be concealed aboveground as artfully as possible. Great fires were lit at the base of some of these shafts, so that the rising air would draw fresh breezes through the tunnels — a practice adopted from deep mines, many of whose engineers Regina had hired to supervise the extension of the Crypt.

But the air shafts alone weren’t enough. There had been a near disaster when a group of five students had been found unconscious, the air in their room foul, a stagnant puddle at the end of a corridor. It had been fortunate for all concerned, Regina thought, that only one student had died — and that her parents, a stoical equestrian family, had been happy to accept the death of their elder daughter as a price to be paid for the safety of their two younger children, both also with the Order. After that incident an elaborate air- monitoring system had been evolved. In every passageway and room there were candles burning, bits of reed dangled from the walls to show the air currents, and caged birds sang in most of the main chambers and corridors.

And it had been found that the simplest way to adjust the environment was by moving people.

A person blocked the flow of air, consumed its vital goodness, and pumped a lot of heat into it besides. So you could improve the flow of air into a problematic region by simply evacuating the passageways around it and moving the people somewhere else. You could likewise cool an area by taking out its people — or warm it up, by crowding more people in. It was impossible to solve every problem by “huddling.” The kitchens, and the nursery and crиche where the Order’s babies were cared for en masse, were a constant difficulty. But on the whole, with careful monitoring and analysis, the system worked well, and was becoming increasingly effective as they learned.

Of course there were many grumbles at this regime of constant shifting, but people had adapted. Space had been at a premium from the beginning, so you weren’t allowed to bring a great deal of personal baggage into the Crypt in the first place. And furniture in each dormitory room was becoming uniform, so it made no real difference where you were.

As far as Regina was concerned, this constant uprooting was an unexpected side benefit. Regina wanted every sister to think of the whole Crypt as her home, not just her own little corner of it.

Meanwhile Order members began to spend an increasing amount of time underground.

In the Crypt there was no summer or winter, and no threats from barbarians or bandits, and no disease, as all the food and water was clean. And it was safe in here, safe and orderly in a world that was becoming increasingly threatening. To the children who had been born here, in fact, it was the aboveground world that seemed strange — a disorderly place where the wind blew without control and water just fell from the sky …

One day, Regina mused, somebody would be born in the Crypt, would live out her whole life underground, and then die here, her body being fed to the great ventilation furnaces, a last contribution to the Order. Regina would not live to see it happen, but she was sure that grand dream would soon be fulfilled.

Regina met Ambrosius Aurelianus seven days later. He stood in the Forum, listening to an orator who declaimed the ruin of the world to a cheerful crowd. He wore the leather armor of a Celtae warrior, even here in the heart of Rome. Ambrosius had aged, but he was much as Regina remembered — the stocky frame, the sturdy, determined face. His startling blond hair was receding, and a deep scar disfigured one side of his face. But his blue eyes held the same warm zeal she remembered from Artorius’s war councils, all those years ago in Londinium.