In Mrs. Harris goes to Paris in the 1950s, widowed housemaid Mrs. Ada Harris (Lesley Manville) falls in love with a Dior couture dress. She decides that she desperately needs a matching dress and goes to great lengths to save up the money to buy it. After suddenly receiving a war widow’s pension, she travels to Paris to do so. She stumbles upon a display of Dior’s 10-year collection and befriends André, the Dior accountant, and Natasha, a Dior model. However, Dior director Claudine resents Ada’s intrusion into the exclusive world of haute couture.