It's September 1914. Ten-year-old tomboy Millie MacCallum has just learned that her father, like so many other Canadian men, will be leaving for England to join in the war effort. More bad her mother has enrolled her in a new school where she'll be expected to learn languages, dancing, and lady-like deportment. Millie would much rather be paddling a canoe or tucking up her dress to wade among water lilies. Nonetheless, she promises her father that she'll stay out of trouble while he's away. But for a girl as lively as Millie, this is a hard promise to keep .