Kirk and the Enterprise have been sent to establish diplomatic relations with the planet Eminiar VII, a planet that decidedly does not wish such relations! But Ambassador Fox insists they make the attempt. Planetside, they learn Eminiar has been fighting a war with Vendikar, another planet in the same system, for five hundred years - a war fought entirely by computers, with casualties required to report to disintegration machines for tidy disposal. And the Enterprise has been declared a casualty of a "tricobalt satellite explosion"; her crew must likewise report for disintegration so their deaths may be recorded and reported to Vendikar.