内容简介：
While the country struggles through the Civil War, sixteen-year-old Emma Truckey struggles through her own battles of self-doubt while living along the shores of Lake Superior in the Upper Peninsula of Michigan. When her father leaves to fight for the Union, Emma's mother takes over his job as keeper of the Marquette Lighthouse and relies on Emma to assist with the keeper duties. In between her chores and the adventures with her friend, Bobby, Emma somehow finds herself mixed up in a wartime spy ring that will ultimately test her confidence and endanger her life. --Based on a true story--