Known in the department for her ability to solve cases with her gut instincts and take-no-prisoners style, Cassie (Sandra Bullock) is saddled with an inexperienced new partner, Sam Kennedy (Ben Chaplin) who plays it strictly by the book. The homicide detectives must find a way to work together as they uncover a trail of shrewdly concealed evidence that links a murder to two young men, Richard Haywood (Ryan Gosling) and Justin Pendleton (Michael Pitt) who believe they may have committed the perfect crime.