Ava Faulkner (Jessica Chastain) is a recovering addict and former soldier turned assassin. In France, she kidnaps her new target, an English businessman. Before she kills him, she questions him on why someone wants him dead. Unbeknownst to her, another woman electronically eavesdrops on the conversation. Afterwards, Ava flies to Boston where she visits with her estranged sister Judy and her mother Bobbi who is hospitalized for angina pain. Ava has not seen them in eight years.