For readers of Emma Donoghue’s The Pull of the Stars and Kristin Hannah’s The Women—a story of a father and daughter on the medical front of the Spanish Flu and World War I, each fighting the same invisible enemy from opposite sides of the world.

When duties collide, how do you choose?

On the Kansas prairie, as The Great War rages in Europe, Dr. Lorne Miller confronts a mysterious illness swiftly killing otherwise healthy adults. As answers remain elusive and fear spreads, his daughter Helen returns home, fresh from nursing school and already planning her return to Boston and the suffrage work that calls to her.

When Lorne makes an agonizing choice he will forever regret, Helen chooses defiance—audaciously joining the Army Nurse Corps and sailing for Europe, carrying a blame she lays squarely at her father’s feet.

From America’s heartland to New York City’s Department of Health and field hospitals in France, father and daughter battle in laboratories and operating theaters: he racing to develop a vaccine as the government suppresses the truth, she discovering purpose in the chaos of combat surgery. Separated by an ocean but bound by love and loss, each must confront the limits of conviction and control, and each must lose everything before they can find what—and who—they cannot live without.