He gives her a dark look. “Of course I remember. I was eight years old, and you told me I was trapped forever because of something bad I’d done. That sticks with you.”

Thora looks away. “Sorry I traumatized you with the truth.”

He turns on her, all teenage anger, a Santi she doesn’t recognize. “How do you know it’s the truth?”

Thora spreads her arms wide. “What else could this be? Take two people who want to go everywhere and see everything, and trap them in one city for the rest of their infinite lives. Seems pretty perfect to me.”

“So what are we being punished for?” he asks her. “What did we do?”

“I told you, I don’t know! Maybe we murdered someone,” she says, half-joking.

Santi shakes his head. “We’re not killers.”

“Speak for yourself.” She takes out a cigarette—correlation or fate, that she always smokes in the worlds where she’s a medical professional?—and lights it. “I feel more murderous every day I spend in this place.”

“If you think it’s a punishment,” Santi argues, “you must think there’s someone doing the punishing. It means you think this is deliberate. Designed.”

Thora snorts. “Well, yes. Discovering reality literally has a wall around it did change my perspective somewhat.” Before Santi can go on, she adds, “I don’t think it’s God, if that’s what you’re wondering. No, this level of malicious fuckery is all too human.”

“Whoever it is,” he says as they pass under the medieval gate of the Eigelstein-Torburg, “if they’re punishing us, there has to be a chance of redemption. They must have designed a way out.”

“I told you, I’ve tried leaving the city a hundred ways—”

“I don’t mean a physical way out.”

Thora smiles. Maybe he’s not so different from the usual Santi after all. “Oh, I remember,” she says. “The right path.”

They enter the tunnel that leads under the train tracks. Santi’s voice echoes back to her strangely. “I don’t think about it that way anymore. If all of our actions matter, that creates too many paths for just one of them to be right.”

“I’m glad we agree.” Thora follows his shadow through the dark. “What are you thinking instead?”

“That there’s something specific we have to do to atone.”

“Atone?” Thora catches up with him as they emerge from the tunnel. “How can we atone when we don’t even know what we’re being punished for?”

Santi lifts his chin. “We’ll know it when we see it.”