Amy Harper Belafonte
Amy Belafonte is the main character of the trilogy. Her childhood is encompassed of her parents abandoning her and the government wanting to do experiments on her. Amy has skills such as talking to animals and Virals, as well as can telepathically communicate. She also has the ability to quickly heal from wounds. She soon tries to discover a cure for the virus, discovering that it is strains carried in various blood samples, and uses that as her goal to try to revert back to normal.
Professor Tim Fanning
He is the original carrier of the disease. He knows of its existence from the beginning of his college since the professor he works with has knowledge of the vampire plague. Fanning goes through many life struggles and challenges such as the woman he loves dying, and experiencing raw humanity. He decided that his fate is to be the monster he is and accept his fate. He is not part of the original twelve but before it.
Giles Babcock
He is one of the virals mentioned in the book. His character is mainly used to establish what exactly are the characteristics that viral beings encompass. These characteristics are composed of insanity, quirky, manipulation, and trouble speaking phonetically.
Anthony Carter
Anthony Carter is the root of irony in the novel. He is someone who was wrongfully convicted, yet everyone is certain that he has ill will. When he gets infected, he takes remorse for every killing he does since it's not his true intentions. In the novel, there is usually a display of bad or good will, but he displays both.