I sensed Kirah’s determination surge through the Ray. “Well, I still think you can convince him, High . . . Anointed Honor. When you walk into a room, he changes. You’re his Core.” She used a stubborn tone that I suspected she got from her mother. “And you know it.” Then she held out four gobs of wax.

Mbali looked doubtful, but sighed, shrugged, and plugged her ears. I plugged mine as well, and Kirah cleared her throat and sang into the rafters. The sound was muted, but I recognized the same lullaby Kirah had sung when we first met, waiting for our turn to be tested in the Children’s Palace.

Even with my hands clapped over my plugged ears, the jangling timbre of Kirah’s voice seeped into my limbs, reminding them of how tired they were. Of how sweet it was to rest. How surely a nap, even here on the cold tiled floor, was precisely what I needed . . .

I shook my head and hummed a counter tune, clearing the fog from my mind. The guards at the top of the stairs were not so lucky. When their shadows appeared on the steps, the four warriors were hunched with exhaustion, yawning as they squinted down at us. Three made it a few steps before slumping in the stairwell, their spears dropping with a clatter as they began to snore. The last guard seemed to realize what was happening, but before she could cry for help I bounded up the stairs, clapped her head, and stole the last few moments of her memories. Guilt pricked me as she stared at my veiled face, her own washed of emotion.

I gritted my teeth and pressed her temple again, erasing the entire morning, as well as the day before. Years of trying to coax away Sanjeet’s nightmares had taught me that minds were dangerously resilient. With enough context, people could reconstruct their stolen memories, like filling in the missing tiles of a mosaic. If Thaddace was to escape, I couldn’t let guards remember who had helped him.

The guard succumbed to Kirah’s song at last, slumping against me. I laid her gently on the landing, then wiped the memories of the three other guards, taking no chances.

How many days of stolen memories, I wondered, did it take to erase who someone was? Suppose I erased a crucial moment or epiphany—was that akin to murder?

I swallowed hard, trying not to think about it. For the few memories I stole from the guards, Thaddace would survive to make thousands more. That made it all right—didn’t it? Sacrifice of the few for the many . . . I shivered, hating the cursed arithmetic of empresses.

One of the guards wore a necklace of keys; I lifted it over his head and lurched up the stairs. There, behind the iron-barred door that led out to Heaven, stood Thaddace, hands clapped firmly over his ears.

I beamed with relief. If Thaddace hadn’t recognized Kirah’s Hallow in time, we would have had to drag his sleeping body from the tower.