Eighth-grader Somali American Nimo Mohamed is the youngest runner on the varsity cross-country team, but she is determined to keep up with the older girls, so she has set herself a grueling training schedule; too grueling because her body is exhausted, her grades at school are slipping, and her father, who is still very much in her life despite the divorce, is starting the pressure her to quit the team.

Lucia loves to watch the monarcas' annual migration with her papa. But this year, their flight north holds extra weight: Papa is heading north, too, to work on faraway farms to feed his family. Though she hates to see him go, he leaves her a song and a promise that when the weather turns cold and the monarcas return, so will he. After many months apart, Lucia watches the skies for a flicker of hope, the monarchs' homecoming that signals Papa's return....