Californians John and Naomi Klaesson have been grieving over the loss of their four-year-old son who fell victim to a rare genetic disease. The effect on the Klaessons is traumatic, and they persuade themselves that by paying a prodigious amount of money to the brilliant geneticist Leo Dettore they can avoid a repetition of the earlier tragedy with another child. What’s more, science (and Dettore) can offer them a raft of new possibilities — possibilities that pose a host of moral and ethical dilemmas. The couple’s second child can be shielded from the genetic defect that claimed their first born, and other advantages can be built into the ultimate designer baby. Long-term Peter James readers will be aware that the author’s career began with just such high-concept ventures (in, for instance, 1993’s Host). So it is no surprise that he is able to skilfully finesse his highly original central notion.