Two days after her husband of 30 years tells her he plans to have an affair, Fiona Maye, a High Court judge who regrets her childlessness, must decide whether or not to grant a hospital’s emergency request to give a blood transfusion to a 17-year-old boy dying of leukemia. He and his parents are Jehovah’s Witnesses who have refused the treatment on religious grounds. McEwan’s latest novel is a powerful reminder that one’s actions often have unforeseen repercussions.