Twelve-year-old Celia Snow regrets the day she convinced her parents to allow her to accompany them on her father's whaling expedition in 1856. Having never been at sea before, she thought it would be exciting, exotic, and thoroughly grown-up. Instead, she begins the voyage terribly seasick and, even worse, homesick.
But when Celia sights her first whale and watches the boats row out to the hunt, she realises that she will see and experience more aboard "The Jupiter" than most girls will in a lifetime. In her heart, though, she still dreams of the day she will return home. But when disaster strikes, Celia must gather all her courage, strength, and newfound knowledge in one desperate attempt to salvage the expedition and the lives of those she loves.