 When Mark and Jesse accompany Amanda to her award in forensic pathology, Alex Vander crashes on their table- he s infected by injection with the highly contagious legionnaires disease, by Ariel, who made him believe to be his lover so he would steal it for her. The doctors have the LAPD (lead by Steve) enforce a strict quarantine while they run an improvised emergency ward, helped by Dr. Herb Downey, a specialist in infectious disease. During the hard work to save lives they must find out all about the sinister plot, which is a very deadly  decoy  for another crime...