If Coma has a theme, it is that doctors are apt to be mad scientists who must be controlled by society before they destroy it. In the book's afterword, Cook bemoans "the failure of society in general and medicine in particular to anticipate the social, legal, and ethical ramifications of a technological innovation. For some inexplicable reason, society waits to the very end before creating appropriate policy to pick up the pieces and make sense out of chaos."
Coma's ghoulish plot stems from the motives of Dr. Howard Stark, who enters the business of selling used human organs in order to finance an expansion of his hospital's research facilities. Stark is the persona of the mad scientist who recurs over and over in Robin Cook novels. The mad scientist's inverted sense of priorities makes medical science an end in itself; Stark offers up human lives in order to further the science of medical technology. "We need people like myself, indeed like Leonardo Da Vinci, willing to step beyond restrictive laws in order to insure progress," Stark raves, explaining to protagonist Susan Wheeler why he must kill her. "What if Leonardo Da Vinci had not dug up his bodies for dissection? What if Copernicus had knuckled under to the laws and dogma of the church?"