In Primordium Book Three: Requiem, the leader of the few remaining humans on Earth dies before building A4-Ni, a universal constructor to spread their genome throughout space. His daughter, Akilah Rasmussen, steps forward to realize his dream. But will she persevere after she discovers that the genome is predestined to be destroyed and the only reason A4-Ni must be constructed is to ensure the creation of an alien craft, the Shepherd?

Following the teachings of Truman Justis of Book Two, future Maraia in the year 10,0005 try to keep their DNA pure while under assault by the evil player Cardassin, a fiendish specimen without compassion or morality.

Fanatically bent on destroying the Maraia and the Shepherd, he waits patiently for the few remaining Maraia to return to their ancestral home of Kanapoi in what was once northern Kenya, where the climate has become inhospitably arctic. They hope to find the exotic guardian of myth that holds the plans to construct A4-Ni, who will create the Shepherd in the distant past.

Aided by the synthetic human, Michael, and the primitive Jamil, Akilah struggles to realize her father's dream, but at a terrible cost.