An observatory floats alone in space. There are no nearby planets or ships. The large structure seems inactive, yet it continually broadcasts a cryptic distress signal mentioning only computer trouble and an epidemic. However, scans reveal no life forms present. Something terrible happened in this place. Many lights are inoperative. Blood stains the floor. The computer runs itself. A rancid stench hangs in the air. And from someplace unseen, a female voice calls out desperately for help.... This is the third book in the Captain Exetre series.