In a near-future city where an authoritarian government controls the media and monitors its citizens, Faith Connors works as a Runner, an underground parkour courier who physically carries sensitive messages to avoid surveillance. When a reformist political candidate is murdered and Faith's twin sister Kate, a police officer, is framed for the killing, Faith races across the city's rooftops to uncover the conspiracy behind the assassination. Her investigation leads her to a private security firm running a covert program designed to eliminate Runners, and she discovers that trusted allies are not what they seem.