Elsidar Beta Tri is a calm, serene planet strategically located between the Federation and the Klingon Empire. Home to the Mijwin, a race of people who have lived in peace with their planet for centuries. But now times are changing. Unwilling to accept any form of technology, the Mijwin have exhausted their world's natural resources and are on the brink of global starvation. When Captain Kirk and the Enterprise arrive to aid the Mijwin, they become embroiled in the race's struggle for survival... A struggle whose climactic battle pits them against each other. with a creature of darkness and darkness - with an entity that roams the corridors of the Enterprise as if it owns them, with an enemy that will not stop at killing to achieve its ultimate goal...