In a tented field hospital on the coast of France, doctors, nurses, and volunteers work together to heal the bodies and souls of men wounded in the trenches of WWI. The hospital is a frontier: between the battlefield and home front but also between the old rules, hierarchies, class distinctions, and a new way of thinking.

Dr. Martin Ellingham is brilliant, dedicated, and highly efficient. He's also brusque, abrasive, and terrified of blood. Once a successful London surgeon, he's now a GP in the idyllic Cornish fishing village of Portwenn, where he's every bit as eccentric as the villagers he serves.

The Knickerbocker Hospital faces an upheaval as Thackery's absence, a death of affluent patients and financial missteps have led the hospital board to decide to shutter the Knick's downtown location and move uptown.