The novel is a captivating life story of an old man from the Channel Island of Guernsey, who narrates his experiences, relationships, and the changes he witnesses on the island throughout the 20th century. Through his eyes, readers are immersed in a rich tapestry of island life, filled with personal triumphs and tragedies, as well as the larger historical events that shape the community. The protagonist's voice is deeply personal and engaging, offering a unique perspective on love, friendship, and the enduring power of place and memory.

The series is a family saga that spans generations, focusing on the lives, loves, and tribulations of the Cazalet family. Set primarily between the 1930s and 1950s, the narrative delves into the personal and societal impacts of events like World War II on the extended family. Through vivid characterizations and intricate relationships, the story explores themes of time, change, and the endurance of family bonds against the backdrop of a rapidly evolving England. Each book in the series captures a different era, reflecting the shifting dynamics within the family and the country at large.