Assignment in Eternity
Description from the back of the book
An agent of the Federal Bureau of Security, disguised as a commercial traveller, arrives from the Moon, carrying with him an incredibly valuable spool of mirofilm. He becomes Captain Gilead, explorer and lecturer. But the transformation fails to deceive those who with to relieve him of the film....and they close in.
Condition - Very Good, Cover has signs of age and the pages are slightly yellow.