The movie is adapted from the book, La banalità del bene – Storia di Giorgio Perlasca [it] (2002) by Enrico Deaglio, about the achievements of an Italian man in saving Jews in Hungary in 1944.

During World War II, Perlasca (a former fascist who changed his opinion about fascism) worked at procuring supplies for the Italian army in the Balkans.

During this period, the Hungarians had forced Jews of Budapest into a ghetto, and they began deporting them to Nazi death camps, even as the Russians advanced on the eastern front.

In post-war Italy Perlasca didn't speak of his efforts to nobody, not even his family, he lived an humble life and his story was unknown until 1987, when the people he saved found him after 42 years of searching him in Spain.

Discovered by a local officer named Glückmar he is arrested (as Italy has surrendered to the Allies, Italian citizens in Hungary are considered enemies).

Another squad of troopers, led by Captain Bleiber, arrive on the scene and arrest some guests, including Italian military officers.

They reach the Spanish Embassy where, thanks to a safe-passage letter signed by Francisco Franco, he gains an audience with the ambassador Sanz Briz.

He begins searching for Magda first in the railway station where the fascists have already started to gather and load the Jews to wagons ready to roll out.

He then visits an Arrow Cross Interrogation base, where he finds a lot of executed Jews but saves those few who survived the torture with Magda among them.

A final raid on the safehouse results in Nagy taking all the Jews (except a half dozen of them who remain in hiding) to the Danube bank, while Perlasca is attending a ball where he tries to borrow a train-wagon for his protégés to be sent to Switzerland.

Upon hearing the news of plans to burn down the Budapest ghetto and its inhabitants, he decides to convince the Jewish community to take up arms and to fight if necessary.

He also makes his final visit to Vajna's office and, with a successful bluff, he convinces him to let the ghetto stand and thus be freed by the Red Army days later.

Bleiber is seen hanged in the street and Perlasca leaves the city with the help of Glückmer, who was originally ordered to arrest him because of his previous fascist affiliations.