The Planet Savers by Marion Zimmer Bradley, A Librivox Audio Boo torrent

The Terran colony on the planet Darkover faces imminent destruction by a plague of the deadly Trailmen's Fever. The only hope is to develop a serum in time, but this requires the cooperation of the elusive native Trailmen, the brilliant parasitologist Dr. Jay Allison, and his split personality. (Introduction by Mark Nelson)
Read by Mark Nelson

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