The film was intended to be a vehicle for Adam West to escape his Batman stereotype by playing a cynical, hard-edged tough guy. The movie's dialogue is typified by a scene between West's Cain and the boozy Mrs. Grinaldi played by Smith:
Mrs. Grinaldi: "And what do you do for a living, Mr. Cain?"
Cain: "I kill people, Mrs. Grinaldi."
The Girl Who Knew Too Much was not a box office success in theatrical release, but became a staple of late-night showings on WCBS-TV and other television stations in the early 1970s. It then disappeared for decades and was in danger of becoming a lost film. However, it finally appeared in a home video release that came on May 28, 2013, on Blu-ray and DVD.[1]