A mysterious letter written by Albert Einstein draws a physicist and a theologian into the Vatican. What they uncover reaches back to Hiroshima—and has implications far beyond science. First Light is an intelligent historical thriller that blends science, faith, and hidden history in a story of discovery and consequence. As long-buried knowledge begins to resurface, scientists confront truths they cannot unlearn, and a chain of events unfolds across decades—from wartime catastrophe to a modern-day auction house, and into the heart of the Vatican. Blending real historical figures with compelling fiction, First Light explores the moral cost of progress, the burden of knowledge, and the collision of faith, power, and human choice.