Citadel of the Green Death

Joel Hakkyt is judged maladjusted and committed to an Experimental Station where convicts serve as living test subjects. His parents and wife sever ties and annulment proceedings proceed while he faces indefinite scientific torment. During transfer he receives a hidden fluorescent tattoo and detects an alien quality in a guard through his unusually acute smell and vision. Recalling reports of Asgard in Alpha Centauri, where native humanoids evade explorers, he confronts the unsettling possibility that a Centaurian presence among the inmates transforms his punishment into a tense mystery of contact, survival, and dehumanizing science.