The Cat o' Nine Tails (1971)

Franco Arno is a blind man that lives with his young niece and makes a living writing crossword puzzles. One night, while walking on the street, he overhears a weird conversation between two man sitting in a car parked in front of a medical institute where genetic experiments are performed. The same night someone breaks in the institute and kills a guard. Arno decides to investigate with the help of reporter Carlo Giordani. (imdb)
Cast and Information
Directed By: Dario Argento
Written By: Dario Argento, Luigi Collo
Starring: Karl Malden, James Franciscus, Catherine Spaak, Horst Frank, Pier Paolo Capponi, Rada Rassimov
Genres: Drama, Crime, Horror, Mystery
AKA: Il Gatto a nove code
Country: France, Italy, West Germany