"Did you bring the key?"

She had laughed. He had not.

And then, at the end of the first aisle: "Leo Cruz, Age 29. Disappeared."

"What key?"

"What did it take?"

The Keeper tilted her head. "He is in the Labyrinth of Unfinished Sentences. But there is a rule, restorer. In the Archivo Román, you may take only one thing. A single document. A single truth. If you take your brother out, you must leave something of equal weight behind."