Spares by Michael Marshall Smith

Set in a dystopian future, the narrative follows Jack Randall, a former police officer who finds himself entangled in a morally ambiguous world where human clones, known as "spares," are bred for organ harvesting. Haunted by his past and seeking redemption, Jack becomes the unlikely protector of a group of spares, leading him on a perilous journey through a society that commodifies human life. As he battles against powerful forces, Jack must confront his own demons and the ethical dilemmas of a world where humanity is both a commodity and a curse.