In the series, bioanthropologist Dr. Sloan Parker discovers that a serial killer's DNA does not match that present within Homo sapiens and learns that there is a new breed of humanity present in the world. This new breed of humans, later classified as "Homo dominant", are attempting to compete with humans and drive them to extinction just as Homo sapiens hypothetically did to the Neanderthals.
The Dominants are known to be smarter and more aggressive compared to regular humans who use any tactic to secure their survival. They are ideologically convinced that, as the superior form of life, they must dominate their environment and all other forms of competition through any means necessary. This aggression seems a near instinctual genetic characteristic as seen when a young Dominant child attacks three older as well as larger human children and on another occasion the introduction of Dominant DNA into a monkey showed the monkey being aggressive as well as killing the other monkeys within the cage. Furthermore, evolution in mental abilities does seem to be present as a Dominant child demonstrated the ability to cloud the minds of others. It was stated by Tom Daniels, a Dominant posing as an FBI agent, that they have the ability to 'sense the emotions' of others which suggests that they may be partial empaths. However, in order to execute their belief in destroying Homo sapiens, the race has somewhat learnt to suppress their emotions as they do not wish to empathize with the species they are dominating. Finally, a mummified remains of a Dominant girl showed that she possessed four uteruses.
It was speculated that global warming and other environmental conditions led to a speciation within humanity and that there were 200,000 members of this new branch of Humanity living in a 'shadow society' among humans who were near blissfully unaware of the threat posed by them. Their point of origin, referred to as their version of 'Eden', was a deserted village in Oaxaca, Mexico which was a sacred location for their kind. It was also the location of a mysterious pillar with arcane writings on its surface.
It is interesting to note that there are groups of humans who are aware of the Dominants and collaborate with them in their attempts. Similarly, there are groups of Dominants who wish to co-exist with their sibling species. It also seems that as part of their infiltration techniques, the Dominants suppress the memory of their own agents to avoid compromises in their security should the agent be captured.
Technologically, the Dominants made use of genetic engineering in an attempt to 'convert' the more numerous humans into more Dominants. They also made use of both cloning as well as nanites in order to achieve their goals. They have also been noted to use extensive brain washing techniques on individuals.