Corrado Invernizzi

as Franco Gozzi

as Luigi - Italian Engineer

as Pietro Calogero

as Lonya

as Il Granduca (voice)

as Giudice Carboni

as Nicola Quinziato

as Laboratory technician

as Concellino

as Preside

as Dottor Cappelletti

as Peter

as Cardinal Angelo

as Pierre Curie

as Lattes

as Le voisin

as Piero Soderini

as Soderini

as Professeur Schultz

as Michele of Cesena

as Cesare