In the distant future, Earth is ruled by the Linnan Empire, led by Lord Adviser Jerrin—until he is poisoned by his scheming wife, Lilidel, in the chaos of an attack by a powerful alien race known as the Riss.

Rather than take his brother’s place and find himself in Lilidel’s crosshairs, the scientist and high priest Clane turns his attention to defeating the Riss with assistance from Czinczar, general of a barbarian army defeated and assimilated by the Linnan years before. Meanwhile, Jerrin’s oldest son, Calaj, is installed as Lord Adviser of Linn, but is wholly unprepared for the responsibility and is quickly corrupted by power and the influence of his mother.

After capturing a Riss vessel during the battle, Clane, Czinczar, and a crew comprised of Linn and barbarian soldiers set off in search of help in their battle against the Riss. After traversing the cosmos for months, they encounter twin planets known as Outland and Inland on which reside agrarian societies of enigmatic humans with remarkable abilities of telepathy and spontaneous teleportation—not to mention an alliance with the Riss!

Clane attempts to forge a friendship with the reluctant Outlanders in order to learn the source of their powers and find a way to use them against the Riss invaders on Earth.

The Wizard of Linn is a sequel to Empire of the Atom, a patchwork novel comprised of short stories focusing on Clane of Linn, who is reviled by the population as much for his physical deformity as for his pursuit of matters beyond their comprehension.

The Wizard of Linn is a stronger and more cohesive story that sees a mature Clane at the height of his scientific prowess. Still, he is not perfect and makes the occasional mistake. The Outlanders find him amusingly incompetent and even upon returning to Earth with the knowledge and technology to potentially rescue the planet from the Riss, Clane is beset by the forces of his nephew Calaj.