Washington, DC, 1950. Everyone keeps to themselves at Briarwood House, a down-at-the-heels all-female boardinghouse in the heart of the nation's capital where secrets hide behind white picket fences. But when the lovely, mysterious widow Grace March moves into the attic room, she draws her oddball collection of neighbors into unlikely friendship: poised English beauty Fliss, whose facade of perfect wife and mother covers gaping inner wounds; policeman's daughter Nora, who finds herself entangled with a shadowy gangster; frustrated baseball star Beatrice, whose career has come to an end along with the women's baseball league of WWII; and poisonous, gung-ho Arlene, who has thrown herself into McCarthy's Red Scare. Grace's weekly attic-room dinner parties and window-brewed sun tea become a healing balm on all their lives, but she hides a terrible secret of her own. When a shocking act of violence tears the house apart, the Briar Club women must decide once and for all: who is the true enemy in their midst?