After many years of small shadowy glimpses and seemingly unassociated encounters, the first X-Files movie (and key episodes in the TV season that followed it) pretty much revealed a full arc of the biology of the aliens that tied all the disparate elements we had encountered to that point together. Here’s my take on the life-cycle of the ‘Roswell aliens’ as revealed in the series.
| Stage 1 (“The Black Oil”, “The Virus”) – The initial stage of alien life has been compared to a virus. Code named in government circles as “Purity”, it exists as an “essence” within an oily black medium. This black oil or black cancer can move under its own power and seems to exhibit a basic, reactive intelligence. It has the ability to exist indefinitely both inside and outside a host. Though principally appearing in the form of pool of viscous liquid, the alien virus seems to actually be made up of thousands of small veriform (worm-shaped) organisms. Normally, the entity enters a human host through the eyes, nose, and mouth. (Thanks to the efforts of the Syndicate, however, the alien essence can also be transmitted through mutated crop pollen carried by bees.)
From its entrance into the system of a host, the virus proceeds to the center of the brain where it collects around the pineal gland of the hypothalamus. Here the individual veriform organisms “feed” upon the chemicals produced by the brain. The effects of this intrusion on the host are immediate, either pushing the individual into a catatonic state or taking over all thought and action. Like the essence itself, the host becomes capable of generating a deadly radioactive pulse. Presumably once inside an intelligent host, the organism takes on the ability for thought and reason in order to coordinate with a larger plan.
Should the host be killed or a more convenient host become available, the black oil can simply exit the organism (again through the eyes, nose, and mouth) and move on. Should the host still be alive after the virus leaves its system, he will not suffer many ill effects from his infection though he will have no memory of the intervening time.
[Successful attempts have been made at creating a vaccine which could combat this virus. Even normal antiviral treatments can affect the organism. More significantly, however, it has been discovered that certain human gene pools are naturally immune to infection by the virus, rendering it as nothing more than a harmless collection of fluid in the brain.]
| Stage 2 (“Predator”) – If a catatonic infected host is introduced into a high-temperature environment, the alien organism is set to enter into the second stage of its life-cycle. The virus within the infected host begins to gestate in reaction to the heat, growing into a full life form from inside the host (a process which can be slowed or even halted with extreme cold temperatures). The growth of this alien form is fueled by its feeding on the entire range of bodily tissue of the host from the inside out. In the end, this process leaves only a gelatinous shell of the original being from which a new bipedal life form violently emerges.
This “newborn” alien stands exceedingly tall with translucent brown skin, large eyes, long fingers, sharp teeth, and retractable claws. At this stage, the alien seems to have little reasoning intelligence and simply acts on an instinct to kill. Though very fast and strong, the alien can be mortally wounded. When killed at this stage, however, the essence of the alien simply seeps out in the form of the black oil to invade another host.
| Stage 3 (“Little Green Men”) – After a short but unspecified time, the infant stage predatory alien begins to seek out an appropriate environment in which it can progress to stage three. Specifically, the alien being requires immersion in a warm- or hot-temperature liquid environment (a heated pool for example). Upon entering, the alien begins to shed its outer skin to reveal a much smaller alien life form with large flat eyes and light green skin inside, the proverbial “little green man”.
The intelligence of the alien at this point seems much higher since these are the aliens often associated with abductions and other alien events on earth. Nevertheless, there still seems to be something childlike in its movements and actions. The aliens are apparently not impervious to harm at this stage either since they have been found killed in crashes and exterminated in government raids using cyanide poisoning. Unlike the stage 2 aliens, however, the death of the alien at this stage is final—there is no more black oil.
| Stage 4 (“The Grays”) – It is unclear how the alien progresses to stage four though an assumption can be made that it simply “grows” into a larger organism in a natural manner. The alien at stage four has reached its culmination—a tall gray figure with a large head and eyes. At this stage, the alien has the ability to “shape-shift” into various human forms. (Thus the ‘bounty hunter’, faceless rebels, and all other humanoid aliens we see are actually morphed grays.)
The aliens bleed a caustic green blood, one that contains a retrovirus fatal to humans when exposed in the air by a puncture wound. [Much like the viral stage of the aliens themselves, this retrovirus is dormant at cold temperatures. Once active in heat, these retroviruses cause the rapid production of red blood cells, clotting the blood and killing the individual.]
These aliens exhibit great strength and can withstand many environments fatal to humans (lack of oxygen, great falls, gunshots, etc.) In fact, the aliens are nearly (but not exclusively) impossible to kill unless they are stabbed in the base of the neck. Because the rebels had to be faceless, it also seems that the aliens can themselves be “infected” by the black oil. [This may not be unheard of—many species that go through stages of growth are deadly in one stage to that of another stage (e.g. bug larvae that eat their parents)]. When killed the aliens simply “melt” away into an acidic green fluid. It is unclear whether the aliens die natural deaths from age or not.