It's 1946. Juliet Ashton, a 32-year-old writer, has found recognition through her light-hearted column in a national newspaper which lifted the spirits of her readers during WW2. But then Dawsey Adams writes to her from Guernsey and, emboldened by their mutual love of books, they begin a correspondence. Dawsey belongs to the "Guernsey Literary and Potato Peel Pie Society", and as Juliet learns more about their reading group, soon she stumbles upon a whole number of islanders eager to write and tell her of their experiences of the German occupation of Guernsey. Entranced by her new friends, Juliet decides to visit the island to meet them properly.