Hurricane Katrina makes landfall in New Orleans. At Memorial Hospital, the doctors, nurses, and staff tend to patients and brace for the storm.

The staff and patients think they’ve made it through the worst—except the waters aren't receding. Reports of a new crisis circulate.

As the city floods, the hospital loses power. Mulderick and the staff attempt to cope with the terrible conditions and prepare for an evacuation.

Conditions continue to worsen. Mulderick, Pou, and more staff grapple with how to best help their patients—and how that help will be prioritized.

With pressures mounting to abandon the hospital, the staff is forced to make challenging decisions.