John Green, the award-winning, international bestselling author of The Anthropocene Reviewed, returns with a story of shattering, unflinching clarity in this brilliant novel of love, resilience, and the power of lifelong friendship. Aza Holmes never intended to pursue the disappearance of fugitive billionaire Russell Pickett, but there's a hundred-thousand-dollar reward at stake and her Best and Most Fearless Friend, Daisy, is eager to investigate. So together, they navigate the short distance and broad divides that separate them from Pickett's son Davis. Aza is trying. She is trying to be a good daughter, a good friend, a good student, and maybe even a good detective, while also living within the ever-tightening spiral of her own thoughts.