Set in a West Country coastal town, the narrative follows Theophilus, nicknamed Taffy, who grows up in a former friary gate-house with a lace-making mother, an ailing grandmother, and a bookish clergyman father. It traces his childhood games and local customs, his apprenticeship and service connected with the lighthouse, and his involvement in a dramatic wreck and the salvage that follows. Alongside friendships, rivalries, and a developing attachment to Honoria, the story examines duty, courage, and moral testing in a close-knit community, using towers and lamps as recurring symbols of leadership, protection, and the light that guides human conduct.