A young woman is sent into danger on a planet poised on the brink of nuclear war, forbidden to interfere with its people's natural course of evolution or to reveal her alien origin. Her fellow-agent is not properly trained to work in the field and his compassion may lead him to intervene, thereby unintentionally bringing about the very disaster that he is trying desperately to prevent. She faces an agonizing choice: side with a renegade agent, ot stop him at any cost.

Although this novel has the same heroine as Enchantress from the Stars it is not a sequel but a completely independent story not intended for readers below high school age.

The 2003 edition contains significant updating and should be read in preference to earlier editions.