In the Third Imperium setting of GDW's Traveller, that vital role is played by the Zhodani, humans transplanted to another world by the mysterious Ancients some 300,000 years before the founding of the Imperium. On their new homeworld of Zhdant (or Zhodane, as the Imperium calls it), the Zhodani developed a unique culture and society, one characterized first and foremost by its open embrace of psionics, a practice the Imperium and its subjects consider morally, not to mention politically, abhorrent. Needless to say, this profound difference has fostered mutual suspicion and animosity between the two peoples and has led to five Frontier Wars.
Alien Module 4: The Zhodani aims to lift the lid on Zhodani society, providing the reader with a clearer and indeed more sympathetic portrayal of "the Psionic Masters" than had previous Traveller materials. By the time of its publication in 1985, the Zhodani were already a well-established facet of the Third Imperium setting, having first been mentioned in The Spinward Marches in 1978 as practitioners of "the Psionic Heresy." Until the early 1980s, when an article about them appeared in the pages of The Journal of the Travellers' Aid Society, the Zhodani were little more than mustache-twirling space opera villains of a somewhat Orientalist cast – the Sassanid Persians to the Imperium's late Romans.
With the arrival of further information on the Zhodani came a more nuanced portrayal. Alien Module 4 is the culmination of that process and it's a generally excellent bit of science fictional speculation. Like previous Alien Modules, this one starts with information on the physical characteristics of the Zhodani homeworld and its solar system. Much more detail is given to the history of the Zhodani, including how they first discovered psionic abilities and the impact it had on their society. In short, the Zhodani learned that some humans are naturally gifted in these abilities and from them arose a noble caste. Those who are not naturally gifted in psionics but who, with training, could become so form the intendant caste. Those who lack psionic abilities form the prole caste. The interstellar state they eventually formed, the Zhodani Consulate, is a democracy with a franchise limited to psionically gifted nobles, making it an interesting mirror image to the feudal aristocracy of its rival, the Third Imperium.
Where Alien Module 4 really shines is in its treatment of Zhodani society and the impact that psionics has had on it. Compared to Imperial humans, the Zhodani is much more peaceable and conformist, in part due to the regular use of telepathy and other abilities to detect "deviant" thoughts and behavior before they become a problem. This is where the infamous – to Imperials anyway – Thought Police have a role. The Zhodani view the Tavrchedl' (or "Guardians of Our Morality") not as policemen but as firemen, whose job is to deal with depression, frustration, and disillusionment among the populace. That the Zhodani have developed advanced means, both medicinal and psionic, to deal with these conditions only makes the Thought Police even more effective.
All the Alien Modules strive to give their subjects their due, presenting them and their societies and cultures from their own perspective. This is very much in evidence in this one's treatment of the Zhodani. Though building on information presented in early '80s Traveller material, Alien Module 4 goes a very long way toward presenting the Zhodani not as stock villains but as solid antagonists with their own plausible point of view, given their starting premises. It does such a good job at this that, when I first read the module, I was somewhat taken aback. I'd spent several years seeing the Zhodani in one way – the Imperial perspective – that I never considered the possibility that there might be another legitimate portrayal of them.
Sympathetic though it may be, Alien Module 4 nevertheless paints a picture of a profoundly alien society, all the more so, I think, because it's peopled by human beings that are physiologically little different from us. The ubiquity of psionics and its effect on Zhodani society cannot be understated. The Zhodani, for example, have little concept of privacy and tend to view Imperial humans as inherently dishonest simply because they will not submit to routine telepathic scans. From their perspective, only someone with something to hide would be worried about such a thing. Likewise, their caste society, based on one's natural mental powers, runs counter to the reader's likely preference for some kind of social egalitarianism (even if the Imperium itself falls short of that ideal as well).
Alien Module 4: Zhodani is thus an excellent supplement for use with Traveller, one that not only provides insight into the Imperium's main enemies but also gives players and referees alike the ability to create and play Zhodani characters. I'm not sure how many people have ever attempted, let alone succeeded, at a Zhodani-focused Traveller campaign, but I doubt it would be very many. Still, the benefit of being able to understand better these antagonists is immense and the Third Imperium setting is richer and more believable because of it.