Italian actress Giovanna Mezzogiorno will play Benito Mussolini’s mistress in helmer Marco Bellocchio’s previously announced “Vincere,” about a child fathered out of wedlock by the 1940s fascist dictator.

Mezzogiorno, recently a lead in Mike Newell’s “Love in the Time of Cholera,” will play beautician Ida Dalser, who ran off with Mussolini before he came to power.

Their child, also named Benito, was kept hidden by the dictator along with Dalser in asylums where both died before Mussolini’s execution in 1945.

Benito fils will be played by Italo thesp Filippo Timi, currently on set with Gabriele Salvatores’ “Come Dio comanda” (As God Commands).

Mezzogiorno also stars in Wim Wenders’ upcoming “The Palermo Shooting.”

Lensing on “Vincere” is set to start this May in Venice and other northern Italian locations. The $13 million historical psychodrama is being shepherded by producer Mario Gianani’s Offside shingle with financing from RAI Cinema, Eurimages and Celluloid Dreams, which is selling internationally.

“Vincere,” which means “to win,” takes its title from that of a popular Fascist-era song. It follows RAI docu “Mussolini’s Secret,” by Gianfranco Norelli and Fabrizio Laurenti, which cast light on this obscure detail in the dictator’s life.