Mrs. Palfrey (Dame Joan Plowright), recently widowed after a long happy marriage, moves into a London residential hotel more lively and elegant on-line than in fact. She determines to make the best of it amongst an odd assortment of people, and she particularly hopes her grandson, a London resident, will visit. When she slips on a walk and is aided by penniless young writer Ludo (Rupert Friend), she invites him to dine at the Claremont and plays along when her dining mates assume he's her grandson. A friendship develops giving her a companion with whom she can talk about memories and poetry and giving him ideas and support for his writing. But what of her actual family? How it plays out is the movie's story.