The second volume in Thompson’s Missing Link trilogy continues to explore ethical issues involving genetic engineering while asking compelling questions about what it means to be human. Teenager Christie accompanies his stepbrother, Danny (part dolphin), Danny’s half-sister, Sandy (part frog), and their father, Bernard, on a trip to Tibet, where Bernard is in search of the yeti. Bernard is convinced the creature holds the key to a missing link in human genetic development and is obsessed with finding out if he is right. Even after Danny is lost at sea, Bernard pushes on while Sandy challenges her father at every turn, clearly unhappy with his single-minded pursuit of scientific advancement without thought for personal costs or the moral implications of his actions. With a deft blend of fantasy and science, Thomson’s fast-paced story also looks at the implications and impact of how humans treat the earth when Danny joins a colony of mer-people who are suffering from a radiation leak, and the yeti that Christie and the others finally meet reveals that she is the last surviving creature of her kind. (Age 12 and older)