NEW YORK TIMES essayist and 2025 Audie Awards® finalist Rebecca Anne Nguyen's stunning debut. In The 23rd Hero, an ordinary woman with an extraordinary memory travels back in time to 16th-century France to stop climate change before it starts and return to the man she loves. In a world ravaged by climate change, a mysterious time travel agency known as the Program sends carefully selected Heroes back in time on missions to prevent environmental damage before it happens. Sloane Burrows secretly longs to be a Hero and restore the natural world of her childhood-a world she can envision with absolute clarity because of her superpower memory. But her father raised Sloane to believe her "freak memory" is a shameful flaw that should be hidden from the world. Sloane stuffs her dream of being a Hero and conceals her memory to the point of making herself sick. Her only respite from the shame is the recurring dream she's been having for nearly a decade. In it, a breathtakingly beautiful man makes her feel accepted in a way she never has in waking life-not despite her memory, but because of it. But when the man in the dream shows up in real life, Sloane's world is turned upside down. Not only is Bastian a flesh-and-blood person, but he's from the Program, and he wants her to do the one thing that will shatter her chances of winning her dad's love: become a Hero, travel back in time to sixteenth-century France, and use her superpower memory to save the world. "A page-turning, wild and marvelous ride." - Susan Choi, Pulitzer Prize finalist and National Book Award Winner for Trust Exercise.