 Michael YorkRobert Dominici | Robert Dominici |
 Edwige FenechHélène Martell | Hélène Martell |
 Donald PleasenceInspector Datti | Inspector Datti |
 Mapi GalánSusanna | Susanna |
 Fabio SartorDavide | Davide |
 Renato CortesiAgent Marchi | Agent Marchi |
 Antonella PonzianiGloria Datti | Gloria Datti |
 Carola StagnaroDr. Carla Pesenti | Dr. Carla Pesenti |
| DDaniele BradoDr. Vanni | Dr. Vanni |
 Caterina BorattoRobert's Mother | Robert's Mother |
| LLewis E. CiannelliChief Physician | Chief Physician |
| RRenata Dal PozzoAgent Corsi | Agent Corsi |
 Giovanni Lombardo RadiceFather Giuliano | Father Giuliano |
 Gianni FrancoInspector | Inspector |
 Marino MaséAging Expert | Aging Expert |
 Achille BrugniniNot listed | Not listed |
 Giovanni TamberiAndrea | Andrea |
 Loris LoddiDanzil, a Cop | Danzil, a Cop |
 Hal YamanouchiSwordmaster | Swordmaster |
 Diego VerdegiglioNot listed | Not listed |
 Raffaella BaracchiLaura, Venice Prostitute | Laura, Venice Prostitute |
| EEmy ValentinoNot listed | Not listed |
 Daniela MerloMother (uncredited) | Mother (uncredited) |
 Raf BaldassarreMan in Police Line-Up (uncredited) | Man in Police Line-Up (uncredited) |
 Rossana CanghiariParty Guest (uncredited) | Party Guest (uncredited) |
 Lella CattaneoWoman at Robert's Piano Concert (uncredited) | Woman at Robert's Piano Concert (uncredited) |
 Ruggero DeodatoMan That Gets on Moped at Station (uncredited) | Man That Gets on Moped at Station (uncredited) |
 Giuseppe MarroccoMan at Robert's Piano Concert (uncredited) | Man at Robert's Piano Concert (uncredited) |
 Benito StefanelliMan in Restroom (uncredited) | Man in Restroom (uncredited) |
