When Joe Wright got on board as director, at first he meant to have the actors say their lines in English. Then he changed his mind and chose to shoot the series in Italian, for a higher immediacy.
Joe Wright used to display music at high volume for the actors and extras to avoid succumbing to tiredness and staying active. For instance, for one crowded outdoors scene, set at Caracalla Thermes, he needed to shoot a long scene at night, involving at least four hundred extras from Rome; due to the night time and the amount of hours of work, in between takes Wright kept preventing everybody from getting tired by displaying techno music, so the place turned into a sort of rave party and the extras felt more "pumped up" and reactive. The director took advantage of that by taking shots of them without telling in advance, to obtain a more spontaneous reaction.
The eponymous TV series is based on the first of four novels by Italian writer Antonio Scurati, a saga on Benito Mussolini until his defeat. This first chapter focuses on the birth and adfirmation of Fascism and Mussolini as a dictator.
Actor Luca Marinelli, who comes from a staunchly anti-fascist family, was initially reluctant to play the part of Mussolini and was embarrassed to tell his grandmother about the upcoming role. When the grandmother asked him why he had accepted the part, Marinelli said he wanted to "share his part of responsibility" in telling this story. When asked in a later interview if he had ever dreamed of playing a historical character, he answered: "Not that one".