Note: The Tor hc and pb have the same cover but different artists credited.

Synopsis: From the front flap of the Tor first edition: Set on the largest interstellar medical installation in the galaxy, replete with engaging human-and-alien interaction and intricate puzzle plots, James White's "Sector General" novels have been a favorite with the SF audience for more than three decades. Now White returns with another entertaining adventure in deep-space medicine. The empathic Dr. Prilicla, a veteran of Sector General for years, is put in command of an expedition answering three distress beacons. What he finds is two hitherto-unknown intelligent species - one of which has nearly wiped out the other - and a revelation of a botched first contact, along with a rare opportunity to set matters right... Assuming, as always, that he can make an accurate diagnosis...