A young scientist, who is trying to invent a practical space-ship, receives a visit one evening from a strange man whose age he cannot determine. The stranger reveals himself as Ahasuerus, the Wandering Jew, who has given most of his 2,000 years to the collecting and collation of human knowledge. He claims that he can give the scientist the formula for a space-drive based on the negation of gravity.

In return, he wants transportation to an alien planet. The scientist, though somewhat incredulous, tries out the formula — and finds that it works. He and the soi-disant Wandering Jew set out for space, and land after an interim on the planet Mars. Here, before they have learned anything about the planet, the Wandering Jew bids him "farewell" and walks off into the Martian sunset, never to be seen again. He has confessed that he wishes to avoid the Second Coming of Christ on earth, which he fears to be imminent. Also, he has exhausted everything earthly.