Four extraterrestrials, X-1, X-2, X-3 and X-4, arrive on Earth in the early sixties. Here they decide to take on human features to study the terrestrials incognito, but end up getting involved in the Roman "dolce vita".
X1
X4
X3
X2
Matilde Bernabei
Lo scrittore di fantascienza
Socio dello scrittore
Cameriere d'Hotel
Cameriera d'Hotel
Se stesso
L'editore
Tifoso di calcio
Ambasciatore austriaco
Lo sposo
Passante che parla con X1
Segretaria dell'editore
Professore di matematica
Sottosegretario esteri
La sposa
Frida, cantante lirica
Marito geloso
Ragazza in bikini
Ragazza francese
Figlia del contadino
Il protettore di prostitute
Ragazza in bikini
Salumiere
Tifoso allo stadio
Ragazza asiatica
Contadino abruzzese
La Grande Mente (voice)
Segretario dell'ambasciatore
Venditore di bibite allo stadio (uncredited)
Narratore (uncredited)
Party Guest (uncredited)
Story
Story
Original Music Composer
Unit Manager
Second Assistant Director
Sound
Line Producer
Production Design
Screenplay
Screenplay
Co-Editor
Director
Director
Costume Design
First Assistant Director
Director of Photography
Makeup Artist
Production Manager
Camera Operator
Producer
Editor
Production Design
Assistant Editor
Hairstylist
Second Assistant Director
Set Decoration
Production Secretary