Inhalt: One summer night, Louisa and her father take a walk on the breakwater. Her father is carrying a flashlight. He cannot swim. Later, Louisa is found on the beach, soaked to the skin, barely alive. Her father is gone. She is ten years old. Louisa is an only child of parents who have severed themselves from the past. Her father, Serk, is Korean, but was born and raised in Japan; he lost touch with his family when they bought into the promises of postwar Pyongyang and relocated to North Korea. Her American mother, Anne, is estranged from her Midwestern family after a reckless adventure in her youth. And then there is Tobias, Anne's illegitimate son, whose reappearance in their lives will have astonishing consequences. But now it is just Anne and Louisa, Louisa and Anne, adrift and facing the challenges of ordinary life in the wake of great loss. United, separated, and also repelled by their mutual grief, they attempt to move on. But they cannot escape the echoes of that night. What really happened to Louisa's father? Shifting perspectives across time and character and turning back again and again to that night by the sea, Flashlight chases the shock waves of one family's catastrophe, even as they are swept up in the invisible currents of history.