This is a realistic fable set on Cape Cod during WW II. Nineteen-year-old Louisa and her much younger brother Jeri are living as refugees on the Cape, their parents having been killed in England. A college professor, Mr. Smith, befriends them, falls in love with her, and learns through them about freedom and action. Bravest (and perhaps saddest) of all is Jeri, who is obsessed with his dead parents and builds a raft on which he attempts to sail back to England to fight the Germans (the Coast Guard rescues him before he gets too far). All the characters, but especially Louisa and Jeri, are a bit too stylized and typecast to ever be thought of as life and blood characters; Nathan uses them more as puppets conveying his wartime message of defeating an enemy of freedom than anything else. He is very good, however, at relating the slow but steady falling in love of Smith with Louisa, which is very tender and sensuous if not so passionate. It's easy to see how this simple love story combined with a call to action against Nazism would be appreciated by readers in 1942 when the book was published.