The story begins in 1939 Czechoslovakia, where we meet Josef, a Czech who deeply despises the Nazis. He is married to Marie, and their world is complicated by Horst, a Czech-German Nazi collaborator who is married to a German woman. Horst frequently brings food and gifts to Josef and Marie, complicating their lives further. Josef's moral stance is put to the test when he discovers David, a Jewish boy who has escaped from a concentration camp in occupied Poland. In a courageous move, Josef and Marie decide to hide David in their apartment, keeping his presence a secret from their unwelcome guest, Horst.
Marie finds herself torn; she often blames Josef for bringing David into their lives, yet she cannot ignore her growing compassion for the frightened boy confined to a closet. To protect themselves, Horst suggests Josef take a job evicting Czech Jews from their homes, a proposal that Josef ultimately accepts, earning him the distrust of their neighbor, Franta, who once tried to turn David into the Nazi authorities.
As the days pass, Marie becomes more attached to David, spending her time learning French with him. Unfortunately, Horst's visits become more intolerable, culminating in an attempted assault on Marie. At the same time, Josef grapples with a personal crisis: he learns he is infertile, leading to a humiliating confrontation with Horst that spirals into a revenge-driven series of events. Horst then demands that they house his Nazi supervisor, a bureaucrat morally shattered after losing his son, but Marie initially refuses because she is pretending to be pregnant.
Faced with the threat of discovery, Josef proposes an outrageous solution: that David impregnate Marie to create a false "miracle" which would divert any suspicion. After much resistance, they go through with the scheme, leading to Marie's pregnancy. As the tides of war turn, Horst's demeanor shifts as well; once suspicious, he now attempts to shield Josef and Marie from the wrath of the German authorities.
As World War II draws to a close and the Germans are driven out, a chaotic situation breeds desperation: Marie goes into labor amidst city-wide turmoil. Josef embarks on a frantic search for a doctor, but the streets are overrun, and the only available doctor is in the grasp of the very people he once aided.
In a twist of fate, Josef encounters Franta, now part of the Czech Resistance, but his past as a collaborator haunts him. Desperate, Josef offers to present David as proof of his true sympathies in exchange for help finding a doctor. When it appears all hope is lost, they discover Horst, whose previous benevolence is recalled as they navigate the dangerous landscape. Horst steps into the role of doctor—much to Marie’s horror—and attempts to help deliver her child as partisans remain skeptical of Josef's claims.
Ultimately, David arrives just in time, answering Josef's desperate plea: > "Let us be human!" The climax unfolds in their home where, against all odds, Marie gives birth to a son. As the dust of chaos settles, David vouches for Horst's changing heart, saving him from peril.
In the aftermath, we see Josef cradling the newborn as he strolls through the ravaged streets, haunted and yet filled with a flicker of hope, imagining David’s lost family and whispering thanks to a son he could never have, finally concluding with an aria from J.S. Bach's St Matthew Passion, interweaving tragedy with a sliver of redemption.
