The Girl Who Knew Too Much/The Evil Eye (Italian: La ragazza che sapeva troppo) is a 1963 Italian-American giallo film directed by Mario Bava, starring John Saxon as Dr. Marcello Bassi and Letícia Román as Nora Davis.

The plot revolves around a young American woman named Nora, who travels to Rome and witnesses a murder.

Several more killings follow, tied to a decade-long string of murder victims chosen in alphabetical order.

[4] An alternative cut titled The Evil Eye was released in the United States and the United Kingdom by American International Pictures; this version features a score by Les Baxter, deletes several scenes, and adds others which place a greater emphasis on comedy compared to the Italian release.

On vacation, American tourist Nora Davis arrives in Rome to visit her elderly ailing aunt, who is being treated by Dr. Marcello Bassi.

Waking up in the hospital the next morning, she reports the incident to the police, who do not believe her after finding no evidence that a murder has been committed.

Nora is assisted by Marcello, who takes her on a sightseeing tour of Rome to distract her from the recent events, as they become romantically involved.

That night, after Marcello drops Nora off at the Craven house, an anonymous call lures her into an empty apartment.

He explains that he collaborated with the police while writing articles about the "Alphabet Murders", leading to the arrest of a mentally ill man named Straccianeve, who denied being the killer.

Nora visits Landini's apartment the next day, finding clues that lead her to believe that he is the killer, including the tape recorder, a confession note on his typewriter and a photo of herself labelled as the possible fourth victim.

[7] Bava was convinced to return to directing by Samuel Arkoff and Jim Nicholson, who had begun co-producing Italian films for release in the United States.

[8] The Girl Who Knew Too Much was the first film in this venture for Arkoff and Nicholson's company American International Pictures (AIP).

The film benefited from AIP as a deal was set between the company and Galatea to have confirmed distribution overseas.

[1] Italian screenwriter Luigi Cozzi has said that the original script was more of a romantic comedy, but the film became more of a thriller as it went into production.

[27] The film's score was by Roberto Nicolosi,[1] who had previously worked with Bava on Black Sunday (1960) and Erik the Conqueror (1961).

[39] The reviewer noted the plot, stating that "Bava, always a better cameraman than director hasn't Riccardo Freda's ability to make a merit of cliches, and often seems rather unhappy with his complicated plot, which is packed to the brim with red herrings, lurking shadows and sinister happenings known to thrillerdom.

[41] James of Blackford Sight & Sound stated, "Although certainly pioneering, The Girl Who Knew Too Much is a low-key, modest film.

It would be Bava's subsequent production, the violent, striking Blood and Black Lace, that would announce the genre's arrival in bold primary colours.