"A newsman works with a blind puzzle-solver to uncover a deadly conspiracy linked to a genetic research facility."
James Franciscus
as Carlo Giordani
Karl Malden
as Franco ArnĂ²
Catherine Spaak
as Anna Terzi
Pier Paolo Capponi
as Police Supt. Spini
Horst Frank
as Dr. Braun
Rada Rassimov
as Bianca Merusi
Aldo Reggiani
as Dr. Casoni
Carlo Alighiero
as Dr. Calabresi
Vittorio Congia
as Righetto (cameraman)
Ugo Fangareggi
as Gigi the Loser
Tom Felleghy
as Dr. Esson
Emilio Marchesini
as Dr. Mombelli
Fulvio Mingozzi
as Spimi's man
Corrado Olmi
as Morsella
Pino Patti
as Barber
Umberto Raho
as Manuel's ex-lover
Jacques Stany
as Prof. Manera
Stefano Oppedisano
as Taxi driver
Ada Pometti
as Telephone operator
Walter Pinelli
as
Sascha Helwin
Marie Louise Sinclair
as Film starlet
Martial Boschero
Cinzia De Carolis
as Lori
Werner Pochath
as Manuel
Tino Carraro
as Prof. Fulvio Terzi
Ettore Arena
as Billiard Player (uncredited)
Aristide Caporale
as Smoker in the Billiard Hall (uncredited)
Giovanni Di Benedetto
as Chief of Police Salmi (uncredited)
Margherita Horowitz
as Lori's Babysitter (uncredited)
Giuseppe Marrocco
as Man at Table in the Saint Peter's Club (uncredited)
Gennarino Pappagalli
as Man in the Terzi's Institute (uncredited)
Aldo Parenti
as (uncredited)
Franco Ukmar
as Policeman - Speaks with Morsella About Food (uncredited)
Dario Argento
Director
Story
Dardano Sacchetti
Screenplay
Luciano Vittori
Visual Effects
Ennio Morricone
Original Music Composer
Salvatore Argento
Producer
Erico Menczer
Director of Photography
Carlo Du Bois
Production Accountant
Luigi Cozzi
Bryan Edgar Wallace
Carlo Leva
Production Design
Costume Design
Luca Sabatelli
Giuseppe Ferranti
Makeup Artist
Vincenzo Marchetti
Assistant Makeup Artist
Pierantonio Mecacci
Maura Turchi
Hairstylist
Angelo Iacono
Production Manager
Roberto Pariante
Assistant Director
Romeo Costantini
Assistant Set Decoration
Franco Pedacchia
Assistant Production Design
Lamberto Verdenelli
Property Master
Eugenio Fiori
Boom Operator
Romano Pampaloni
Sound Recordist
Mario Ronchetti
Sound
Massimo Anzellotti
Sound Effects Editor
Roberto Bertozzi
Electrician
Roberto Brega
Camera Operator
Arturo de Castelterlango
First Assistant Camera
Rodolfo Flibotti
Gaffer
Giuseppe Gabrielli
Grip
Maurizio La Monica
Second Assistant Camera
Alberico Loreti
Best Boy Electric
Renato Mascagno
Ettore Migalizzi
Giovanni Migalizzi
Maurizio Migalizzi
Key Grip
Firmino Palmieri
Still Photographer
Francesco Rachini
Carlo Vinciguerra
Cesarina Casini
First Assistant Editor
Sergio Fraticelli
Assistant Editor
Bruno Nicolai
Conductor
Administration
Roberta Leoni
Production Secretary
Title Designer
Luciano Anzellotti
Sound Effects
Franco Fraticelli
Editor
Giuseppe Mangogna