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?