Sixteen-year-old Noa has been cast out in disgrace after becoming pregnant by a Nazi soldier and being forced to give up her baby. She lives above a small rail station, which she cleans in order to earn her keep. When Noa discovers a boxcar containing dozens of Jewish infants bound for a concentration camp, she is reminded of the child that was taken from her. And in a moment that will change the course of her life, she snatches one of the babies and flees into the snowy night.

1942. Hannah Martel has narrowly escaped Nazi Germany after her fiancé was killed in a pogrom. When her ship bound for America is turned away at port, she has nowhere to go but to her cousin Lily, who lives with her family in Brussels. Fearful for her life, Hannah is desperate to get out of occupied Europe. But with no safe way to leave, she must return to the dangerous underground work she thought she had left behind.

Young Adelia Monteforte flees fascist Italy for America, where she is whisked away to the shore by her well-meaning aunt and uncle. Here she meets and falls for Charlie Connally, the eldest of the four Irish-Catholic boys next door. But all hopes for a future together are soon throttled by the war and a tragedy that hits much closer to home.

Life is a constant struggle for the 18-year-old Nowak twins as they raise their three younger siblings in rural Poland under the shadow of the Nazi occupation. The constant threat of arrest has made everyone in their village a spy, and turned neighbor against neighbor. Though rugged, independent Helena and pretty, gentle Ruth couldn't be more different, they are staunch allies in protecting their family from the threats the war brings closer to their doorstep with each passing day.

Brought to the peace conference by her father, a German diplomat, Margot Rosenthal initially resents being trapped in the congested French capital, where she is still looked upon as the enemy. But as she contemplates returning to Berlin and a life with Stefan, the wounded fiancé she hardly knows anymore, she decides that being in Paris is not so bad after all. Bored and torn between duty and the desire to be free, Margot strikes up unlikely alliances: with Krysia, an accomplished musician with radical acquaintances and a secret to protect; and with Georg, the handsome, damaged naval officer who gives Margot a job.