Asta and her younger sister, Pieta, have watched in terror as Hitler's invasion spreads across Europe. Eventually, the war arrives in their city, bringing with it destruction and death. As the Nazis clash with Stalin's Red Army and relentless bombing rains from above, the girls flee to their grandparents' farm in the countryside. But no place is safe. Surrounded by enemies, Asta and Pieta are presented with one chance at escape: a transport ship leaving from the Baltic Sea.

Getting from the farm to the coast is an impossible trip through a brutal war in the dead of winter. With food scarce, warm clothing lacking, and few resources, the sisters have little chance of making it. And Asta and Pieta are not alone in their plans—everyone is headed to the harbor with the same desperate hope. Securing a place on the ship will require nothing short of a miracle. Their dangerous journey is only just beginning, though, and the sisters can't begin to imagine what they'll have to sacrifice to survive . . .