Kevin Burkhoff (Jeffrey Combs) was a world-renowned neurochemist before suffering a mental breakdown. He was committed to Abendson Psychiatric Hospital, where he remained until he was awakened by a device constructed by Tess Doerner, a 4400 and fellow patient.

After checking himself out of Abendson, Burkhoff began doing neurological research on the 4400. His research helped expose a government conspiracy -- the 4400 had been unknowingly receiving injections of promicin inhibitor, a substance designed to prevent them from gaining extra-human abilities. But the inhibitor was making them sick, and Burkhoff's discovery led to their eventual cure.

Burkhoff subsequently immersed himself in the study of promicin, which included injecting it into his own body. He eventually became the first non-4400 promicin positive, developing the ability to heal himself. He also experimented on an unwitting Diana Skouris, but the experiment didn't go as planned. When NTAC swooped in and attempted to arrest him, it was the ability of the recently released Tess that helped him evade capture.

Kevin and Tess were recruited by Jordan Collier to join his movement. It was Kevin's research that enabled the distribution of promicin, fulfilling the prediction that he would become "the father of 4400 technology."