Based on the award-winning documentary of the same name, this medical drama follows the staff members in the nation's busiest emergency room as they cope with a staggering influx of patients, which can outweigh their limited resources, resulting in a condition known as code black. Residency Director Dr. Leanne Rorish -- who is known for her success with high-risk procedures in the trauma area -- leads residents Malaya and Angus, among others. Senior nurse Jesse Sallander manages the residents and serves as Leanne's confidant, with doctors Rollie Guthrie, Will Campbell and Heather Pinkney rounding out the group. Together, the doctors and nurses race to save lives in an overwhelmed system.