Barbara Carey flies to Italy to visit her blind sister Mary Ann, who is studying in a music academy. Once in Rome Barbara discovers her sister has disappeared and, according to the Italian police, she may have been murdered by a maniac who is obsessed with young sightless women. With the help of Martin Foster, from the British Embassy, Barbara starts trying to find out what happened to Mary Ann. She even pretends to be blind herself in an attempt to attract the killer, and finally the clues lead her to Seagull Island, privately owned by a mysterious British citizen named David Malcolm. Barbara must then find the answers to several questions: was Mary Ann really kidnapped? What happened to David's wife and son in the island? And why is David's relative Carol so unhappy to see a woman with him?
| Directing | Nestore Ungaro | Director |
| Art | Giuseppe Mangano | Art Direction |
| Crew | Germano Natali | Special Effects |
| Production | Rebecca Howard | Casting |
| Sound | Mario Dallimonti | Sound Mixer |
| Camera | Mario Bagnato | Camera Operator |
| Production | Federico Tocci | Location Manager |
| Production | Eleanor Kearney | Production Coordinator |
| Writing | Augusto Caminito | Writer |
| Editing | Angelo Curi | Editor |
| Directing | Antonio Gabrielli | Assistant Director |
| Sound | Graham Harris | Sound Editor |
| Production | Nestore Ungaro | Producer |
| Sound | Bill Rowe | Sound Re-Recording Mixer |
| Sound | Christopher Lancaster | Sound Editor |
| Lighting | Marcello Gabriele | Gaffer |
| Sound | Tony Hatch | Music |
| Sound | Mike Le Mare | Sound Editor |
| Sound | John Poyner | Supervising Sound Editor |
| Sound | Decio Trani | Boom Operator |
| Camera | Daniele Nannuzzi | Camera Operator |
| Camera | Giulio Diamanti | Key Grip |
| Camera | Mario Tursi | Still Photographer |
| Production | Robert Mandell | Production Coordinator |
| Production | Adrian McCarthy | Production Assistant |
| Production | Bob Kellett | Associate Producer |
| Editing | Gunter Glinka | Editor |
| Art | Gianni Giovagnoni | Assistant Art Director |
| Costume & Make-Up | Angela Silighini | Seamstress |
| Crew | Abe Mandell | Creative Consultant |
| Writing | Jeremy Burnham | Writer |
| Art | Robert Conforte | Graphic Designer |
| Art | Armando Scarano | Property Master |
| Production | Gérald Morin | Production Assistant |
| Production | Lucio Trentini | Production Supervisor |
| Costume & Make-Up | Bona Nasalli-Rocca | Wardrobe Supervisor |
| Sound | Alan Willis | Music Editor |
| Costume & Make-Up | Aldo Signoretti | Hairdresser |
| Writing | Nestore Ungaro | Writer |
| Editing | Tony Lenny | Editor |
| Costume & Make-Up | Franco Corridoni | Makeup Artist |
| Sound | Peter Pennell | Sound Editor |
| Directing | Marion Mertes | Continuity |
| Camera | Armando Nannuzzi | Director of Photography |
