Patients at a Maryland hospital face an outbreak of a horrifying "flesh-eating" disease that spreads quickly and continues to kill as Dr. Connor and his elite team desperately thrash around looking for a common cause that could affect so many. Meanwhile a mother frets over her athletic young daughter (as Danielle, guest star Shannon Woodward) who faces a leg amputation. As Dr. Durant conducts tests comparing the patients' blood, Connor buys time with high-powered antibiotics and tries to think outside the box in pin-pointing its unlikely source.