The first English language stand-alone edition was published as an E-book by Gollancz's SF Gateway imprint on September 29, 2011, as part of a general release of de Camp's works in electronic form.

Herculeu Castanhoso, assistant security officer at the Terran spaceport of Novorecife, looks on disapprovingly as his detested boss, security chief Afanasi Gorchakov, fraternizes in the spaceport bar with three new arrivals to the backward planet Krishna: the vainglorious amateur poet Brian Kirwan, psychologist Gottfried Barr, and missionary Althea Merrick.

Althea has been left stranded and without resources because the unreliable Bishop Harichand Raman, her superior in the Ecumenical Monotheist Church, has failed to meet and provide her with her first assignment.

Kirwan, bound with Barr for a utopian Terran colony on the island of Zesh, is trying to persuade her to join them, while Gorchakov is pressuring her to marry him.

Trying to prevent a fight between the two, Althea is caught between them and knocked out, whereupon the security chief fells Kirwan and peremptorily orders Castanhoso to get the other men out of the bar.

She is to be Barr's assistant in his project of measuring the intelligence of the primitive tailed Krishnans of Zá, the island adjacent to Zesh, whose culture has recently made startling advances.

The three take flight by buggy down the Pichide River to the coastal fishing village of Qadr, whence they cross by ferry to the Free City of Majbur.

Althea tells Kuroki of the coming attack, but he refuses either to leave Zesh, take any defensive measures, or even to warn the Záva from whom the colony rents its land, citing his group's principles of pacifism and neutrality.

In the days that follow all three grow increasingly disenchanted with the colony, and decide to inform the Záva of the impending invasion themselves in return for passage out of the war zone.

Sofkar, the Dasht of Darya, has her bound to the mast with orders that she be killed if her story proves false, and takes his ships into the harbor.

The latter claims Althea; she appeals to Raman but he declines to defend her on the grounds that she is married to the security chief and has compromised her reputation by running off with Kirwan and Barr, as well as by going around naked (which is common behavior in this tropical climate).

He also reveals the secret of the Záva's intelligence; when younger, he had been taken to Earth and given the experimental "Pannoëtic treatment", which turns lower primates into geniuses while driving human beings mad.

Yuruzh may have been the unnamed tailed Krishnan resident at an Earthly scientific institute in de Camp's earlier Viagens story "The Colorful Character".

Another instance of de Camp's use of a "lower" species raised to intelligence by scientific means can be found in his earlier short story "The Blue Giraffe" (1939).