According to Bobby Rupp, this was a movie that murder victim Nancy Clutter wanted to see. He mentions this in the book 'In Cold Blood' by Truman Capote.
This originally began as a Broadway play written by "Midnight Cowboy" author James Leo Herlihy which opened at the Playhouse Theater on February 27, 1958, ran for 166 performances and closed on July 19, 1958.
Although it was initially scheduled to be released in the U.S. as "Blue Jeans," the title was changed to "Blue Denim." National Screen Service did print up posters with the original title, but they are rare. Some foreign markets used the "Blue Jeans" title in translation.
The original Broadway production was billed as a comedy.