At the heart of Miss Sloane—and a cool heart it is—lies a question. Why does the title character walk out on her lucrative career as one of D.C.’s highest-paid lobbyists to join an underfunded nonprofit in its quixotic attempt at changing some gun laws? The question keeps the movie from falling into the easy do-gooder outline of Erin Brockovich. Elizabeth Sloane (Jessica Chastain, all stiletto-heel precision) might possibly be stirred by a sense of social justice, but she might also just want to win a game that everybody tells her is unwinnable. We’re talking about an alpha female who isn’t content with mere victory—she gives you the impression she also wouldn’t mind hearing the lamentations of women (and men) on the field of battle. It’s crucial to this movie’s crisp watchability that we’re not sure what motivates her battle plan. Maybe battle is just her thing.