A Los Angeles Times newspaper ad from Oct. 1957 shows that Universal Pictures widely distributed this film as "Forbidden Interlude" on a double bill with L'uomo dai mille volti (1957) starring James Cagney.
Rossano Brazzi spoke excellent English and had, by 1957, appeared in a number of American and British films. However, he is, in this movie, clearly dubbed during a few scenes by Paul Frees, although, for most of the time, the voice heard is Brazzi's own.
Frequently reported as having been based on James M. Cain's story "Serenade," but this film's plot and characters bear absolutely no resemblance to Cain's tale, which was filmed one year before by Warner Bros. starring Mario Lanza and Joan Fontaine.
Remade in 1968 by Columbia Pictures, in which the role of the librarian was transformed into that of a reporter.