Jagernauts have extensive biomech throughout their bodies, allowing for enhanced speed and reaction, and an embedded artificial intelligence (AI) in their spinal cords.

They are pitted against the legions of the Trader empire, in particular the Aristo ruling class, a race that derives pleasure from the amplified pain and anguish of empaths—especially Jagernauts, as Soz knows from personal experience.

From Jaibriol, Soz learns that his father is going to commit genocide against the inhabitants of a planet who have joined together to rebel against their Aristo rulers.

In the second section, Soz is sent by her brother, Kurj, the imperator of the Skolian Imperialate, for rest and recuperation on the planet Foreshires Hold.

They hide on an isolated planet, with only Soz's father and the president of the Allied Worlds of Earth aware of their true situation.

In 2008, Asaro rewrote the entire book and gave the revised version to the Baen Free Library to post.

[2][3] The sequel to Primary Inversion is The Radiant Seas, which continues the story of Soz, Jaibriol, and Kurj and is written as an epic space saga covering nearly twenty years.

A portion of Primary Inversion is devoted to Soz's attempts to deal with the emotional repercussions of being both a highly sensitive empath and an advanced military weapon.

James Schellenberg at Challenging Destiny Reviews has noted that Asaro "understands one of Roger Ebert's dictums about what makes for interesting drama, namely that it's not what we do, but how we feel when we're doing it", and that Soz is "a strong, dynamic character, one that people of either gender can easily identify with.

[7] In 1996, Asaro published a paper in the American Journal of Physics called "Complex Speeds and Special Relativity" that gives the mathematical formulation she developed for the fictional star drive used in Primary Inversion.

Primary Inversion and its sequel, The Radiant Seas, deal with interstellar combat from the perspective of relativistic space travel.

The battles in Primary Inversion and other of Asaro's works include extrapolations of current-day ideas in bio-cybernetics, artificial intelligence, situational awareness, relativistic complications, and weapons development.

[4][11] The presence of empathy (in Rhon) and anti-empathy/sadism (in Aristo) is explained by two extraneous structures in the brain, KEB and Kyle Afferent Body (KAB).

The main character, Sauscony Valdoria is a warrior, a Jagernaut (biomechanically enhanced fighter and pilot) with the rank of a Primary (military status equivalent to general) and very tough.

[13] The label assigned to the book has become a source of controversy, in particular due to the blend of hard science with romance in the Romeo and Juliet tale of love between the scions of two empires.