Trivia

Bob Morris (Stephen Crane) drives a 1941 Cadillac convertible; Police Lt. Barry Lane (Barton MacLane) drives a 1938 Ford sedan.

This was the first directorial assignment of Henry Levin, who went on to enjoy a long and surprisingly varied career, encompassing such diverse titles as Journey to the Center of the Earth (1959) the original 1960 version of Where the Boys Are, two Pat Boone musicals (Bernardine and April Love) and two of Dean Martin's 1960s Matt Helm spy spoofs (Murderers' Row and The Ambushers).

During the opening credits (and scenes early in the film), in order to get the wolf to repeatedly open and close its mouth as if it were barking or chewing, they put a rubber band around its muzzle.

Detective Barton Maclane claims he discovered female fingerprints, suggesting the murderer was a woman. Many in the audience thought such a possibility absurd, but such a determination is possible through analysis of size and the amino acids left in the sweat of the fingertip ridges revealed in the print, though this research only appeared in 2015.

This was the first film for which Nina Foch received top billing. She would go on to a decades-long career, often playing character parts. She had featured roles in "An American in Paris" and "The Ten Commandments", among many other famous films, got a Best Supporting Actress Oscar nomination for 1954's "Executive Suite" and, in her later years, conducted acting classes for aspiring young thespians in West Hollywood.