An alien virus introduced into Earth's environment to eliminate potentially hazardous threats. The Theta Virus targeted humans with Ultra potential, causing a lethal breakdown of their cellular structure and eventually death. Dr. Rachel Deming found a cure, using recombinant messenger-RNA sequencing to save the lives of Theta infectees. A side effect was that 99% of those people treated by Deming also manifested Ultra powers. She brought these Ultras together to become the Exiles.