In Miami, the Homicide Unit responds to a scene to find the 911 caller covered in blood and a 35-year-old woman brutally stabbed. Before Det. Fabio Sanchez can determine if the 911 caller is a witness or a suspect, the case takes a dramatic turn when a second stabbing victim turns up at a local hospital. And in DeKalb County, Det. Joe Renaud and his team are working the shooting murder of a 22-year-old man. With no witnesses, the team hopes piecing together the last hours of the victim's life can lead them to the killer.