Lighthouse Girl, at the outbreak of World War I, Fay's isolated life on bleak, windswept Breaksea Island takes a dramatic turn. As a lighthouse keeper's daughter, Fay knows semaphore and Morse code and responds when the soldiers on the ships signal to her. Soon, the soldiers are semaphoring messages for their loved ones, which Fay then telegraphs on their behalf.
 
Although they never meet, Fay eventually becomes friends with one young soldier who has no family. After the soldiers depart for the battlefields of Egypt and Gallipoli, Fay follows their fortunes and continues her long-distance conversations with them through letters and postcards. Drawing on archival material and interweaving fact with fiction, Fay's tale is based on a true story and brings to life the hardships of those left at home during the war.