Running footsteps closed on us. Hive workers, of course, drones, most of them women, all of them dressed in dust-covered smocks. Faces swam before me in the uncertain light, gray eyes troubled. I grabbed Lucia’s hand, and she clung to me just as hard. “Go,” I shouted at the drones. “Get out. There may be more falls. Take the stairs. Go, go . . .”

The drones hesitated, turned, fled, and we followed.

The long climb up stairs of cut stone and steel was a nightmare of darkness and billowing smoke. It got worse when more drones joined us, and we became part of an immense file of women, children, a few men, all clambering up those narrow, suffocating stairwells. The power was down in some sectors, and by flickering emergency lights I glimpsed people running, collapsed partition walls, smashed glass. In the hospital areas, and in the strange chambers where the mamme had lived, squads of people were working busily, pushing beds and wheelchairs out of damaged rooms. But the air thickened rapidly, and it became stiflingly hot; the ventilation systems must have failed.

I just pushed my way through the mobs of drones. My only priority was getting out of there: myself, Lucia, and the baby, for not once did I release her hand.

It was only when I got aboveground that I got a clear sense of what was happening.

Peter had placed his Semtex skillfully. He had broken open the upper carapace of the Crypt. The result was a great crater, collapsed in the middle of the Via Cristoforo Colombo, with a plume of gray-black tufa dust hanging in the air above it. Workers from the nearby offices and shops, clutching their cell phones and coffees and cigarettes, peered into the hole that had suddenly opened up in their world. There was a remote wail of sirens, and a lone cop was doing his best to keep the onlookers away from the hole.

And the drones simply poured out of the crater, in baffling numbers, in hundreds, thousands.

Dressed alike, with similar features, and now obscured by the dust, they looked identical. Even now there was a kind of order to them. Most of them came out over one lip of Peter’s crater, in a kind of elliptical flood. At the edge of the ellipse were heavier, older women, some of them with their arms linked to keep out strangers. At the center of the mass were the younger ones, some cradling infants, and here and there I saw hospital workers carrying the heavy chairs of the mamme-nonne. Nobody was in the lead. The women at the fringe would press forward a few paces, blinking at the staring office workers, and then turn and disappear back into the mass, to be replaced by others, who probed forward in turn. As they reached the buildings at the sides of the road the flowing ellipse broke up, forming ropes and tendrils and lines of people that washed forward, breaking and recombining. They probed into doorways and alleyways, swarming, exploring. In the dusty light they seemed to blur together into a single rippling mass, and even in the bright air of the Roman afternoon they gave off a musky, fetid odor.