Brothers Paul and John Andersen detonate a bomb in downtown Oslo, then cross the fjord to Garden Island, where a girls' empowerment assembly at a summer camp is underway. There, posing as police, they systematically murder 91 children in the name of white supremacy. Scottish expat Cal Curtis and his Norwegian wife, Elsa, wait desperately with other parents on the shore, until they are called to identify a girl, who turns out not to be their older daughter, Licia. Nearly a year later, the police haven't made any progress in locating Licia, and Cal and Elsa face a widening gulf in their marriage. Meanwhile, their younger daughter, Vee, throws herself into investigating her sister's disappearance. When she locates a videographer who documented the island attack from a helicopter, it becomes clear that the Oslo police chief, Ephraim Tvist, has been harboring secrets, prompting Cal to lobby for the chief's removal. But Cal doesn't anticipate the gut-wrenching twist that will bring the brothers' evil mission still closer to home. Cal's outsider perspective adds a layer of alienation to the family's rising anxiety, all of which adds to the oppressiveness of the bleak Scandinavian landscape. As it becomes clear that Vee is hiding something about what led up to the tragedy, McPherson sensitively explores a family in crisis. Highly recommended for book groups.