Lanark is the alter ego, or transformed version, of Duncan Thaw. Duncan is an obsessive, unappreciated artist consumed with a monumental project. Plagued with disfiguring eczema that becomes a metaphor for the larger human engineering projects of the Institute, Duncan stands for the singularity of the creative individual as humankind's hope against totalitarian domination. As Lanark, a doctor and Rima's lover, he is caught up in a doomed, idealistic crusade that ultimately takes his life.

Rima is presented primarily as Lanark’s love interest. As their involvement deepens, she also gives birth to their child. Also in danger of being overtaken by the scaly dragon identity, Rima escapes that fate with Lanark's aid. Nevertheless, she chooses instead to go with Sludden.

Professor Ozenfant is the malevolent director of the Institute. Working his way into fame and power from his scientist beginnings, he stands for the corruption of supposedly objective science. His depiction as a music lover amidst inhumane experiments emphasizes his hypocrisy.

Sludden is the ultimate politician. Ostensibly a principled radical opponent, he soon reveals his devotion only to his own advancement with lip service to the powers that be. With his seductive charms and polish, serving as a foil to the naive Lanark, Sludden takes Rima from him.