Dr. Mara Okafor hadn't slept in forty hours. On the quarantine moon Cessil-9, eleven mine workers had each spoken one strange word into the comms log, then gone quiet. When they woke, they answered to other names and wept for cities nobody had ever heard of. Their blood was clean. Whatever this was, it wasn't in the blood. It was in the voice. The comms log blinked on her screen, waiting to be played.

Mara played the log. Eleven voices said the same word: a wet, clicking sound her own throat tried to copy before she clamped her mouth shut. She slapped the speakers off, heart pounding. The word wanted to be repeated. That was how it spread. She had to know where it came from.

Mara sprayed her own throat numb so she couldn't speak the word and be turned. But now she couldn't call for help either. The med bay door slid open behind her, and eleven workers stepped out, smiling. She backed toward the lab, mute, with nothing left to fight them but her hands.