In Mason’s sequel to Primordium Book One: Reformation (2015), a scientist travels back and forth through time, caught in a conflict between cosmic entities to control a genetic strain that seeded mankind.

Except for some time-travel seesawing to the 71st century, this story is set in 2005, 20 years after an important incident in northern Kenya. During that event, an organic spaceship called the Shepherd clashed with an amnesiac, damaged version of itself over the possession of Gilomir, a powerful alien genome sequence. It was stored in ancient primates as an act of desperation, and as a result, it provided the evolutionary spark and intelligence that created the human race. Now the Shepherd has returned to Earth (or, more precisely, another Shepherd, due to time travel) because “players”—ruthless, self-recycling agents of the Zug, the dark side of Gilomir—are at large there. One has taken the form of a beautiful woman and the other, a hulking Neanderthal; both are trying to control the genome and ensure that the human race devolves back into primal apes. Protagonist Truman Justis, meanwhile, is the half-Kenyan son of one of the previous book’s casualties. His remarkable resume as a fighter, geneticist, and Zen disciple makes him the likeliest hero to save humanity, if he’ll embrace his destiny. Along the way, the small cast of characters appears as different versions of themselves in alternate and/or parallel world-lines. This book has a more action-driven aesthetic than the earlier installment’s science-as-poetry lyricism, although the Gilomir, as a concept, is starting to resemble the Force of Star Wars fame. Overall, it’s a time-hopping game of capture-the-Gilomir, with the same violent events often re-running from a different point of view. As one character says, “time loops are confusing,” but science-fiction readers who enjoy having their minds stretched like a pack of Silly Bands may enjoy the many deliberate pummelings of déjà vu.

A complicated sci-fi sequel featuring many puzzling time loops.

In Mason’s debut sci-fi novel, a tormented anthropologist looking for the origins of mankind meets a not-quite-human girl who reminds him of a lost love.

This work impressively shuttles backward and forward through the cosmos, speculating on humanity’s remote past and destined future, while largely remaining bound to the same setting: a few arid square miles in northern Kenya in 1985. That’s where John Lohner, a Harvard paleoanthropologist on an excavation site, tries to forget about the tragedies in his life—specifically, his mother’s suicide, his own suicide attempt, and the death of his fiancee, Diane, in a traffic accident. The fact that Lohner hears voices in his head doesn’t make things any easier. When he and his African assistant, Kamau, find an unnaturally pale, hairless, and nude girl, Mia, in a field, he’s shocked to find that she reminds him of Diane. Readers, however, already know that Mia, perceived by natives as a “witch,” is actually a synthetic humanoid—a sort of ephemeral scout created by a mysterious, spaceborne entity called the Shepherd, which travels through time and space by using black holes. Four million years ago, the Shepherd clashed with a marauding artificial intelligence called A4-Ni over the custody of Gilomir, a precious, sentient genome sequence. The two wounded combatants tumbled to primordial Earth, where Gilomir sowed the seeds for intelligent Homo sapiens. Now the Shepherd and A4-Ni, with inhuman patience, near a showdown, in which Lohner unwittingly plays an important part. In lesser hands, this obtuse material could have gone completely off the rails. However, Mason doles out the story’s mind-stretching revelations, on an Olaf Stapledon–like scale, and pathos with fair skill, keeping the narrative’s key features carefully hidden or flat-out confounding. In his flights of imagination, he sometimes spins sheer prose-poetry out of genetic-science terminology, practically singing of haploids, nucleotides, chromosomes, and amino acids (“A4-Ni stored her methodology in a genetic lockbox she constructed in his Y chromosome”). A sequel, Primordium Book Two: Renaissance, has already been published.

An ambitious tale with compelling concepts but one that’s dauntingly dense—even for sci-fi readers raised on the temporal loops of Doctor Who.