The overnight crew becomes immersed in a bizarre car-accident rescue. Drew serves overseas in Afghanistan and teams with a colleague to treat an Afghani woman, A spunky grad joins the shift.

TC and Scott fight to save a boy and his mother who were injured in a car accident, yet it becomes clear there's more to the family dynamic than meets the eye. Deployed in Afghanistan, Drew and Syd face the aftermath of an OR shooting.

In part one of this two-part season finale, Scott and Jordan face grave danger during a rescue mission at a rapidly spreading wildfire outside San Antonio. Tensions are high between Syd and TC as they find themselves in the middle of a humanitarian crisis on the Syria-Turkey border. Paul and Shannon argue over treatment for a patient. Meanwhile a major setback threatens Drew's adoption plans for Brianna, Topher struggles to find a buyer for the hospital and medication goes missing.

Drew, his mom, and Rick's flight home turns into a medical crisis at 35,000 feet when passengers become sickened one by one. Jordan, Paul, Shannon, Kenny, and Cain spend their day off at an obstacle course fundraiser for Cystic Fibrosis, hosted by Akbar Gbajabjamila. Scott finds himself on a Tinder date he won't soon forget. Meanwhile, TC puts his own life in danger to operate on a soldier.

When protestors descend on a funeral for a dear member of the night shift family, multiple veterans are injured and brought to San Antonio Memorial for treatment. A high profile politician from Drew's past triggers flashbacks to his time in Iraq. Jordan, Scott, and TC disagree on how to best provide care for the politician. Paul and Shannon must improvise while tending to Doug, a former POW. Cain and Drew treat a fearless photographer.