A mathematics professor finds his reality fracturing when he begins to experience memories of lives he never lived. Masterson, a man struggling with alcoholism, discovers that his life is being manipulated by unseen forces that treat human existence as a series of random, probabilistic events. As he attempts to regain control over his own consciousness, he must navigate a world where the boundaries between objective reality and subjective perception are systematically dismantled. The narrative utilizes a third-person perspective to track his descent into a reality where his professional expertise in probability becomes his only tool for survival against an existential threat.

Readers frequently highlight the novel's ability to blend complex mathematical concepts with a fast-paced, paranoid thriller atmosphere. Discussion often centers on the effectiveness of the protagonist's internal struggle as he attempts to reconcile his academic background with the irrational events unfolding around him. Critics note that the collaboration between Pohl and Williamson results in a narrative that prioritizes intellectual inquiry alongside traditional science fiction tropes. The pacing is often described as relentless, keeping the reader engaged as the stakes escalate toward an uncertain conclusion. Many readers appreciate the focus on the fragility of human perception when confronted with forces beyond individual comprehension.