In 1941, after Hitler declares war on the United States, unleashing U-boat submarines to attack American ships, Louisa June, with the waves outside her house carrying dangerous enemies, must help her mother after her father and brother are caught in the crossfire.

When Sonia's father loses his job and she must move from her small, supportive private school to a public middle school, the half-Jewish half-Indian sixth-grader experiences culture shock as she tries to navigate the school's unfamiliar social scene, and after her father is diagnosed with clinical depression, she finds herself becoming even more confused about herself and her family.

Middle schooler Natalie's year-long assignment to answer a question using the scientific method leads to truths about her mother's depression and her own cultural identity.