Hans Rebka intends to solve the galaxy's most persistent mystery. He is going to penetrate Paradox. Many have entered Paradox before Hans Rebka, but no one has ever left, at least not with mind intact. But as a troubleshooter, Hans Rebka is in a class by himself, though he doesn't know it, he's about to uncover the secret of the Artifacts--and loose the most hideous menace ever encountered.

Convergent Series 1998, Baen Books

ISBN-13: 9780671877910

Unitary edition

Mass-market paperback