The Immari
The Immari Corporation is an evil organization that advocates waiting the plague out and allowing it to ravage the world, killing off the weak and revealing the strong who have evolved beyond humanity. They are power-hungry and opportunistic, taking over the countries who have already been devastated by the plague and planning to build a new world order by allying themselves with the strong survivors. This corporation is a symbol for the stance it takes: transhumanism at the cost of human lives. It represents the power and danger of embracing this philosophy, and its ultimate defeat at the end of the third novel reflects the truth that the philosophy is ultimately unsustainable and unethical.
The Orchid Alliance
The Orchid Alliance is an organization that forms as a response to the Immari, fighting to keep humans alive with the Orchid drug, which holds off the effects of the Atlantis plague (although it doesn't cure the disease itself). This alliance engages in war with the Immari, representing the opposite philosophy: the valuation of human life above its evolution. The Orchid Alliance is a symbol for resistance to this philosophy and the embrace of the innate value of human life.
Dr. Kate Warner
Kate herself is a symbol for something very similar to the Orchid Alliance: she stands for taking a stand against the devaluing of human life and fighting for what is right. Being a superhuman Atlantean (inhabited by Janus, the Atlantean who gave humans the Atlantis gene in the first place), Kate becomes the archetype for her point of view, standing in opposition to Dorian, the other Atlantean on the planet, who agrees with the Immari.
Dorian Sloane
Dorian is a former officer in the Nazi stronghold in Antarctica, and he is resurrected at the beginning of this novel by Ares, the other Atlantean, who actually inhabits Dorian himself. He and Kate are the only two Atlanteans in the human race, and they become more important than simply themselves; they become symbols of their world views. Dorian is the opposite of Kate: he rejects the claim that human life is valuable as it is, and he works to ensure the transcendence of the strong in this new phase of human evolution.
The Ark
The ark in Malta is supposedly the epicenter of the Atlantis plague. Being the catalyst for the disease, it represents the capacity of humanity for either great or terrible things. It provides a safe haven with its protective radius, implying that the natural response is good rather than evil, but it certainly allows the opportunity for great evil to exist as well.
