Before he suicidally blasts his spaceship into a star to confront a dangerous cosmic irregularity, Supreme Commander Jack Commer resigns his commission, elevating genius physician/engineer Laurie Lachrer to take his place as leader of the United System Space Force. But now, inexplicably transported along with him, forced to share his ship's doom, Laurie struggles to assert herself as the new supreme commander.

The five crewmembers aboard ship deteriorate in the unbearable cosmic radiation of the Anomaly at the center of the universe. But the Fools of the Fire who maintain infinite watch over the Anomaly will speak only with Laurie.

Meanwhile fascist elements overthrow the United System and declare Laurie a traitor. Naïve alien university students on an Alpha Centaurian planet mount a resistance in tandem with Laurie's identical robot counterpart, Laurie 283, who builds Pegasus, a state-of-the-art flying saucer weapons platform, to restore Supreme Commander Laurie to power. Mickey Mal Michaels, a decades-old robot with a malfunctioning Sublayer Four who's also in love with Laurie, writes Fathom the Doomboat Stars, "the greatest science fiction novel ever written," to assert his own control over the narrative.