It was the contention of one galactic historian that similar planets must have similar histories. It was the contention of another that this did not imply identical histories. The challenge could only be settled by actual testing in the infinity of the cosmos.
The computer came up with the story of Joan of Arc on the Planet Earth. Programmed anew, it produced a similar world, the Planet Noldaz of Sigma 32, with a human race rising from medievalism among whom a maid would appear to lead her country’s knights on a war of liberation.
The question: was she inevitably doomed to die at the stake, as Joan had before her? Did identical situations always mean identical conclusions?
Pierre Barbet, master of alternative histories and parallel worlds, spins a marvelous science fiction novel out of one of the great enigmas of history.
Captain Setni, of all the officers of space, was the most immune to hypnotic suggestion and psychological delusions. Hence, when reports reached the Great Brains of a strange new planet in the Hydra group, Setni was the logical astronaut to check it out.
Because by all accounts the planet seemed a double of Old Earth—but of Earth as it had been in the far past—and legendary beings were alive and well there.
Setni was specially trained for the task, but even the best training in disbelief was not sufficient. For on that pseudo-Earth, not only was Charlemagne in power and knighthood in flower, but the pagan gods were visible, physically real, and devilishly active.
Setni knew it was no illusion—
but then what was the reality?