In a future where many sources of enjoyment have been banned, along with riding animals, and a religion dedicated to the Light rules, young Thomas has just come of age. A vicar, needing to make up a quota, whisks him away from Little Pond for Teaching. Sitting in a dark cellar, scantily fed, lectured by vicars, Thomas steadfastly promises to protect light from dark. Then he's told he can return home - provided he gives the names of anyone in Little Pond who is breaking rules.

In THERE COMES A PROPHET Orah, almost of age, is a weaver girl in Little Pond. She and a farmer boy called Nathaniel are Thomas's friends. Worrying about his prolonged absence, they can do nothing to help. When Thomas returns, he is thin, hollow-eyed and bitter, saying little. It takes most of the winter for him to start talking to his friends again. Then Orah is taken for Teaching and Nathaniel, panicking, rushes after her to the city where he offers to take her place. This has never happened before, and while decisions are being made Nathaniel speaks with an old man who is imprisoned for speaking his mind - that the feared religious carry on Teachings as a way to control the populace. They instill limits instead of providing possibilities. He asks the boy to take with him a secret which guards the remnants of the past. Released, the two collect Thomas and leave Little Pond, searching for the truth.

What starts as a simple adventure story changes to give the characters recorded definitions of words such as politics, religion and theocracy. I thought that at this point the characters ceased to be quite such individuals and became people learning and deciding to spread the same message. Clearly David Litwack is hoping that young adults will think for themselves and try to understand better why different parts of the world are governed the way they are, or follow the teachings they do, and decide what they want to have in their own lives. The hidden keep which stores the previous era's science is compared to the knowledge preserved by monasteries during the Dark Ages of Europe. THERE COMES A PROPHET reminds us that people who challenge the status quo - like young people everywhere - are not always welcome.