The principal aim of the book is to present an engaging narrative that appeals both to scientists and non-scientists. A mixture of memoir and biography, it tells a deeply human story. Although informed by the importance of neutrinos, it is primarily about Fred Reines, and not technical details of neutrino physics. The science presented here is intended to appeal to a broad audience. Essential to the story about Reines, the science is described in a manner intended to interest and excite the reader. While coursing through Reines’ life and the varied challenges and encounters he experienced, the book also reveals the constants of his persona.