“Play it again, Marcus. And don’t tell me I’m imagining the frequency.”

Lucian Aldridge didn’t look like a man who had just been granted a medical miracle. He looked like a man haunted by a ghost he could finally see but couldn’t touch. He was pacing the length of the library—the room that had once been his sanctuary and was now his interrogation chamber. The mid-morning sun streamed through the high windows, illuminating the dust motes that danced in the air like tiny, silent stars.

Marcus Langley stood by the mahogany desk, his gloved hand resting near the small, silver digital recorder. He had found it tucked beneath the dust...