Samantha Mack is a Chicago cop with a drinking problem, a married lover and blood on her hands. On an impromptu sting operation, her ex-partner Fred Maloney is shot dead with her gun. Sam remembers firing her gun at the perp, a suspected child molester, until it was empty, but when she wakes up in hospital, there is no evidence that there was anyone besides her and Fred at the scene, alive or dead.
