The Headmen are a group of criminal masterminds, each of whom has undergone an experiment or accident that gave him or her a radically abnormal physical appearance, who have banded together for mutual gain.

Each member of the Headmen believes that his or her intellectual talents qualify him or her to rule the world, but that those talents have been scorned by society at large. Hence, Dr. Arthur Nagan organized the Headmen, so that, combining their abilities, they could take control of the planet through peaceful means, entailing secret political and economic machinations.

Besides Nagan ("Gorilla-Man"), the members of the Headmen are Dr. Jerold "Jerry" Morgan ("Shrunken Bones"), a biologist, Harvey Schlemerman, alias Chondu the Mystic, a minor practitioner of the mystic arts, and scientist Thursday Rubinstein, alias Ruby Thursday. Of the four, only Chondu had a normal human appearance when he first joined the Headmen.

Seeking to exploit the superhuman abilities of the group of adventurers called the Defenders, Nagan transplanted Chondu's brain into the body of Defender Kyle Richmond, alias Nighthawk. Richmond later regained his own brain through surgery performed by Dr. Tanya Belinskaya, while Chondu was given a new, inhuman body by his fellow Headmen.

First Collective Appearance: DEFENDERS #21.