The ceiling glows.

Not with fire. There is no fire. No torches, no oil lamps, no braziers. The light comes from within white panels stretched across the vault, pale and flat, and it is cold, unwavering, without shadow. I have stood in the Pantheon at noon when the sun pierces the oculus like Jupiter’s eye. This light has no source, no direction, no god behind it.

I put my hand on a pillar. Stone, but wrong somehow, too smooth. I wait for my legs to remember how to stand.

The girl is beside me. Still here. Still watching.

The space stretches before us like the Basilica Julia during a trial, vast and echoing. The columns are not columns but flat surfaces covered in glowing pictures that move. Faces appear and vanish. Symbols fall past, falling, falling. Images of objects I cannot name cycle endlessly. Advertisements, I realize slowly. They must be advertisements. Even in the underworld, someone is trying to sell something.

People flow around us like the Tiber in flood. Hundreds of them. Thousands. All in black. Gray. The whole crowd dressed for a funeral. They walk with a purpose I can’t read, eyes fixed forward or down at the glowing rectangles in their hands. No one speaks. No one pushes. In Rome, a crowd this size would be a riot of noise and elbows. Here, they move around each other without touching, without acknowledging.

The silence is the worst part. Beneath the humming of the ceiling-lights and the strange chimes from the metal barriers ahead, there is no human sound. No hawkers crying wares, no slaves calling to each other. The dead would be louder than this.

Where am I?

A woman’s voice speaks from everywhere at once.

I flinch before I can stop myself, reaching for a gladius that isn’t at my hip. The girl grabs my sleeve and pulls, hard. She’s pointing upward. Not at the glowing ceiling, but at the panels on the walls that bear strange symbols.

「次の山手線は…」

The goddess, she must be a goddess, to speak without form, to be heard by thousands, continues her pronouncement. I don’t understand a single word. The symbols on the panels shift as she speaks. An omen? Instructions from the divine?

The girl releases my sleeve. Her face is pale, but her eyes are moving again. Taking inventory. She’s looking for something. Exits, maybe.

Think like a merchant. Assess the situation. What do I have?

Nothing. I have nothing. My toga marks me as foreign. My coins are worthless, if I even still have coins. I have no clients here, no contacts, no language. I have a child who cannot understand me and a purple arrow above my head that marks me for… what? What does the arrow mean?

I try again.

“Puella,” I say carefully, using the simplest Latin I can manage. I point at myself. “Marcus.” Then I point at her. “Tu es…?”

She stares at me. Then she speaks. Sounds I can’t separate into words, tones that rise and drop, syllables that end before I can grab them. She points at herself, repeats something. “邵嫦.”

I try to echo it. “Shao…?”

She nods, once, sharp. Then she speaks more, gesturing at the space around us, at the people, at the metal barriers ahead. What is this place? How do we get out?

“Nescio,” I tell her. I don’t know. “Nescio.”

Her face tightens. She turns away, and for a moment I think she’s going to walk off, find her own way, leave me as the lightning-man did. But instead she watches.

She watches the crowd flow toward the barriers. She watches each person approach the waist-high gates, pull something from their clothing. Small, flat, like a tessera. They touch it to a glowing circle on the metal. The barrier chirps, a sound of permission, and opens. The person walks through without breaking stride. The barrier closes behind them.

This happens again and again. A hundred times while we watch. No one passes without the offering. No one.

One man approaches too quickly, reaches for his tablet too late. The barrier screams. Refuses to open. He stops, embarrassed, searches through his bag while the crowd splits around him, rejoins on the other side, ignores him. When he finally finds his tessera and touches it to the circle, the barrier permits him through.

The girl, Shao, tugs my sleeve again.

She points at a person approaching the gates. Makes a small gesture: something in hand. Touch. Then she points at the open gate. Then she points at us, at our empty hands, and shakes her head.

Clever girl. Quick.

I nod to show I understand. We cannot pass. We don’t have whatever token these people carry. We’re stuck.

Now what?

Shao starts walking toward the barriers, and I follow. Perhaps there’s another way. Perhaps the guards, there are guards, men in dark uniforms standing at wider gates to the side, will let us explain. I can mime, gesture, make them understand that I am Marcus Valerius Maximus, and I need—

I need what? To go home? There is no going home.

We’re halfway to the gates when I feel it, the feeling I get when a customer’s about to pull a knife instead of a coin purse. Something has changed. The crowd is still flowing, still silent, but there’s a gap forming around us. People are looking now. Not at us, at the space above our heads.

The arrows. They can’t see them, we’ve already established this, but something about us. The clothes. The standing still. The not-knowing-where-to-look.

Two of the uniformed men have turned toward us.

They’re not running. They’re not drawing weapons. But they’re walking like vigiles toward a disturbance, and their eyes are on us.

I have handled officials before. I know how to stand straight and lie with my posture. But these officials don’t speak my language. They don’t know my name. And I have a purple arrow floating above my head.

Shao has gone very still beside me.

I step forward. Just slightly. Enough to put myself between her and the approaching guards. She doesn’t move away.

The guards are ten paces from us when I see him.

On the other side of the barriers, beyond the gates. Standing still while everyone else flows past. Looking directly at us.

Lightning-man.

His strange clothes catch the ceiling light, throw it back in pieces. He looks tired. Not surprised, though, not even a little. He sees me. The guards. Shao at my shoulder, trembling.

His mouth moves. Words I can’t hear. Then he raises one hand.

Beckoning? Warning? I can’t tell.

The officials are five paces away now. One of them is reaching for something at his belt.

And lightning-man is still watching, still waiting, his hand still raised—