London of 1946. Juliet is a charismatic and very liberal writer who receives a letter from a member of a mysterious literary club that was founded in the Nazi-occupied city of Guernsey. She is immediately attracted to the content of that letter and keeps on looking forward to further exploration, so she immediately decides to go to that city for a visit. There she meets the delightful and eccentric members of the literary club, including Dawsey, a robust and intriguing farmer who has sent him that letter. As the secrets of their past wartime warfare, Juliet attaches itself increasingly to the island, to the members of the literary group, and especially to Dawsey, and the course of his life will be changed forever.