Invariant


Fiction - Time Travel
380 Pages
Reviewed on 06/10/2025
Buy on Amazon

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    Book Review

Reviewed by Golder Hazelton for Readers' Favorite

Invariant by A.G. Sullivan boldly asks: “What would you change if given the chance?” This is a lush, seamless, and complex yet accessible narrative encompassing many elements: a mysterious dying man, a cryptic list (seemingly in code), an undulating journey toward clarity for anti-hero David, who cannot let unanswered questions lie, his love interest Hannah, whose arrival in his life was predicted by the list a full year before they met, experimental government programs, dead scientists shrouded in mystery, shadowy figures from the past, and an emotional journey across the full diapason of human emotions – joy, profound grief, confusion, guilt, triumph, defeat, and even across the boundaries of life and death.

The narrative is vibrantly descriptive but always fluid and lightning-quick. The characters are rendered with a many-layered emotional and psychological precision – even the peripheral characters have fully realized inner lives, clear agendas, and a rich subtext. The protagonist, David, is so eminently human that he becomes a sort of modern Everyman, offering affirmation for those in the real world cycling alternately between elation, contentment, and despair. David’s love interest, Hannah, is an equally compelling portrait of strength and fragility. Tragedy makes an appearance, as do redemption, catharsis, and a sterling and noble moral to finish the tale (optimists, hang in there and keep your eye on Nella). It would be impossible for any reviewer to discuss or even mention the connection of the title to the narrative and the moral without destroying the element of surprise as this epic tale coalesces into resolution. Suffice it to say that absolutely no one will be disappointed with Invariant’s deeply satisfying and unexpectedly perfect ending. Invariant by A.G. Sullivan is a masterfully crafted, thought-provoking tale full of romance, suspense, intrigue, and no small amount of wonder, ideal for anyone who expects a little something extra from their time spent reading.