In 1963, while Americans were raving about Elizabeth Taylor in “Cleopatra,” Italy was pioneering a new genre of film called “giallo.”

At its most fundamental, giallo incorporates suspense, sexploitation and horror. “La ragazza che sapeva troppo,” also known as “The Girl Who Knew Too Much,” is acknowledged as the first giallo film.

This film, directed by Italian filmmaker Mario Bava and starring John Saxon and Letícia Román, is about an American tourist, Nora, who visits her elderly aunt in Rome. After her aunt passes away, a series of events entangles Nora in the midst of several bloody killings. Upon witnessing what Nora believes to be a murder on the Spanish Steps, she finds herself delirious and is hospitalized after losing consciousness.

Nora’s struggle to recall what she saw that night yields an interesting series of plot twists and suspense.

Although some may argue that giallo predates “The Girl Who Knew Too Much,” this film truly marks the arrival of the Italian genre. At the time the film was produced, European jet-setting was newly popularized, and the depiction of Nora’s journey to Rome captures the excitement of traveling the world while simultaneously showcasing famous Italian landmarks.

“The Girl Who Knew Too Much” received recognition for its stylish look as it was the last black-and-white project Bava directed. The film also highlights giallo’s literary origins by incorporating the reading of a giallo novel in the opening scene.

This film is dramatically different from the modern horror film, relying less on gore and violence to scare the audience. “The Girl Who Knew Too Much” is a classic film about mystery, murder and suspense.