Secrets & Lies (1996)

A 27-year-old optometrist who was adopted goes looking for her birth mother and finds Cynthia, a lonely, jittery woman in a gloomy rowhouse who never expected to be found. Mike Leigh lets scenes run long, and the first meeting between Marianne Jean-Baptiste's Hortense and Brenda Blethyn's Cynthia is one of the great two-hander scenes in British film. It won the Palme d'Or, and Blethyn took Best Actress at Cannes. This is the pick for families shaped by adoption, or by any secret kept too long; it is frank about the hurt, but it ends with people choosing each other.