Taraji P. Henson does her best to breathe life into this generic actioner, bringing warmth and humor to the underwritten title role. The top assassin for a Boston organized crime family, Mary develops a maternal interest in the 13-year-old son of a man she’s killed, taking the boy in and protecting him from thugs who want him dead. She also sets off a gang war by killing the head of a rival family, and when her superiors find out, they send another assassin after her. Director Babak Najafi (London Has Fallen) fails to generate any suspense—even the shoot-outs lack excitement—and the drama between Mary and her young charge feels canned. With Danny Glover, Billy Brown, and Rade Šerbedžija.