A magazine editor is found dead in her mansion; Megan confronts a suspect while at a social event with her mother; Ethan surprises Kate with his positive attitude.

When a young nanny is run down by a car and killed, the 5-year-old child she was watching is kidnapped; an interrogation goes awry.

When a recent lottery winner is found brutally murdered, everyone becomes a suspect.

When a city-wide outbreak of a mysterious and lethal virus occurs, even Megan and her team are at risk. In order to determine who and what caused this outbreak, CDC Officer Charlie Stafford takes over the investigation.