Wasp.

You could summarize this story as action/adventure and still do it a disservice. This is about an agent dropped on an enemy planet with one goal: to disrupt, distract, and generally raise hell with the planetary administration in a textbook example of unconventional psychological warfare. Russell had a theory that one man can, with minimal support, completely discombobulate a planet to the point where its military effectiveness would be severely diminished. This book is his theory expressed as a novel.