 Michael BrandonRoberto Tobias | Roberto Tobias |
 Mimsy FarmerNina Tobias | Nina Tobias |
 Jean-Pierre MarielleGianni Arrosio | Gianni Arrosio |
 Aldo Bufi LandiPathologist | Pathologist |
 Calisto CalistiCarlo Marosi | Carlo Marosi |
 Marisa FabbriAmelia, the Maid | Amelia, the Maid |
 Oreste LionelloThe Professor | The Professor |
 Fabrizio MoroniMirko | Mirko |
 Corrado OlmiPorter | Porter |
 Stefano Satta FloresAndrea | Andrea |
 Laura TroschelMaria | Maria |
 Francine RacetteDalia | Dalia |
 Bud SpencerDiomede / Godfrey | Diomede / Godfrey |
 Dante CleriCoffin Salesman | Coffin Salesman |
 Guerrino CrivelloRambaldi, the Neighbor | Rambaldi, the Neighbor |
 Gildo Di MarcoPostman | Postman |
 Tom FelleghyPolice Commissioner Pini | Police Commissioner Pini |
| LLeopoldo MiglioriMusician | Musician |
 Fulvio MingozziMusic Studio Manager | Music Studio Manager |
 Stefano OppedisanoBearded guy with girlfriend | Bearded guy with girlfriend |
 Pino PattiFuneral Exhibition Attendant | Funeral Exhibition Attendant |
 Ada PomettiExtra (credit only) | Extra (credit only) |
 Jacques StanyPsychiatrist | Psychiatrist |
| FFortunato CeciliaFuneral Exhibition Visitor (uncredited) | Funeral Exhibition Visitor (uncredited) |
 Franz ColangeliFuneral Exhibition Visitor (uncredited) | Funeral Exhibition Visitor (uncredited) |
 Shirley CorriganGirl at Party (uncredited) | Girl at Party (uncredited) |
 Luigi CozziMasked Killer in Theater (uncredited) | Masked Killer in Theater (uncredited) |
 Giovanni Di BenedettoFuneral Exhibition Attendant (uncredited) | Funeral Exhibition Attendant (uncredited) |
 Sandro DoriFuneral Exhibition Attendant (uncredited) | Funeral Exhibition Attendant (uncredited) |
| RRenzo MarignanoFuneral Exhibition Attendant (uncredited) | Funeral Exhibition Attendant (uncredited) |
