Tim and Kate Welch are seemingly the last middle-class family in the exclusive neighborhood of Brooklyn Heights, New York. Tim is a popular history teacher, and an ordinary guy. Kate is not ordinary, but she aspires to be. Brought up by a hippie mother, Kate stays home with their two young sons trying to be the responsible parent she never had. But their neat and tidy world is turned upside down when Anna Brody --- beautiful, wealthy and impulsive --- moves into the most expensive brownstone in Brooklyn, and draws Kate and Tim into her world.

January 1946: London is emerging from the shadow of the Second World War, and writer Juliet Ashton is looking for her next book subject. Who could imagine that she would find it in a letter from a man she’s never met, a native of the island of Guernsey, who has come across her name written inside a book by Charles Lamb. As Juliet and her new correspondent exchange letters, Juliet is drawn into the world of this man and his friends --- and what a wonderfully eccentric world it is.