Book Description
"The Federation considered itself a technological Utopia--and the planets under its sway were guaranteed stability by the power of the time-change teams. For whenever there was evidence that a new-found world might evolve into a menace, a team of seven were sent to tamper with that world's past history. But the seven that went to Ygone encountered a fate no theorist had projected. They met with immediate ambush; they found a culture that could not be fathomed, and they were finally confronted with all the contradictions that the system of time-tampering implied."--Back cover.