After ten years serving in the Earth's government's military, Everett Cole wasn't exactly sure what he'd signed up for when he left his birth planet.

Clarity came on the colony planet Astrild after teaming with an enigmatic colleague named Edgar Millen. Their agency employer works to influence colony planets to eventually join the Federation, the largest human political entity. But there are opponents: individuals, parties, criminal enterprises, and competing interstellar dominions. Astrild lacked the planetary government needed for development in preparation for Federation membership. Although the agency used various strategies, Cole and Millen were tasked with removing obstacles hindering that development—obstacles not amenable to diplomacy and reasonings—the methods left undefined by their employer.

Their first assignment had been to rouse citizens to expel a criminal gang that had taken over a small town named Justice. After success at Justice, their second assignment on Astrild was merely to observe and report on an area settled largely by religious sects—an area named Edna whose original purpose was to show sect colonists living in peaceful harmony—an Eden of tranquility. Unbeknownst to Millen and Cole, Justice and Edna were part of a larger conspiracy to keep Astrild from joining the Federation.

In Edna, a serpent lay in wait for them, an evil that, if left unchecked, could infect all of human civilization. Millen and Cole's capacity for violent solutions, when needed, would be put to the test.