Joanna can't get over how her brother broke his promise to never leave like their dad did. Sam is thousands of miles away on a navy ship, and no matter how often he sends letters, Joanna refuses to write back. But then President Kennedy comes on TV with frightening news about Soviet missiles in Cuba - and that's where Sam's heading. Suddenly Joanna's worries about being home alone, building up the courage to talk to a cute boy, and not being allowed to go to the first boy-girl party in her grade don't seem so important. Maybe sometimes there are good reasons to break a promise. The tense timeline of the Cuban missile crisis unfolds alongside a powerful story about what it means to grow up in a world full of uncertainty.