Vornan-19 fell from the sky, naked, and landed on the Spanish steps in Rome on Christmas afternoon toward the end of the Millennium. And for Leo Garfield things would never be the same. For he is an acknowledged expert in the time reversal properties of sub-atomic particles... and Vornan-19 claims to come from far in the future. Whether or not he is telling the truth, a nervous and edgy world accepts the charming and magnetically charismatic Vornan as some kind of messiah. Even Garfield and his fellow scientists fall under Vornan's spell. But, has he really traveled across time — or is he just a charlatan and a fraud? A compassionate and powerful novel worthy of comparison to Stranger in a Strange Land.

It was published in the United Kingdom under the title Vornan-19.

Nominated for Nebula Award for Best Novel in 1968.