Pregnant nurses at James Madison Hospital beg to be relieved from caring for patients with the Zika virus that is raging through a hot Philadelphia summer. But Mother Burgess, the Director of Nursing refuses. So the nurses turn to Lenny Moss for help joining his service workers union. But Lenny has his hands full investigating repeated attempts to murder Rachel Austin, a popular doctor. As the epidemic overloads the hospital with cases, and the administration retaliates against the nurses who are leading the union campaign, a killer roams the facility with murder in his heart.