On 2 Jan 1968, DV announced that Steve Broidy of Motion Pictures International (MPI) had negotiated a co-production deal with Mexico’s Producciones Anco to develop the William Douglas Lansford script, The Big Cube. Lindsley Parsons would serve as producer with executive producer Francisco Diez Barroso. According to a 6 Jun 1968 DV article, Parsons worked with Emilio Rabasa of the Mexican National Film Bank to be able to shoot the picture entirely abroad, which would dually serve to bolster Mexico’s profile in the competitive international film market and bring the total production cost down to around $560,000—an estimated $300,000 less than if it were made in the U.S. In this and other news items, Parsons defended his decision and bemoaned the inordinate size and rules of Hollywood unions, drawing vocal criticism from union representatives for driving work away from American technicians.
       Principal photography began 3 May 1968, as confirmed in a 28 Jun 1968 DV production chart. The unit was headquartered at the Estudios Churubusco in Mexico City, while a 4 Jan 1968 DV brief indicated location work would also allegedly be completed on the Mexican coastal island of Cozumel. Filming was expected to last eight weeks.
       The 25 Apr 1968 DV stated that The Big Cube would mark the first feature film appearance of fashion model Karin Mossberg under a new acting contract with MPI.
       Prior to the film’s release, a 19 Nov 1968 DV article announced that distributor Warner Bros.—Seven Arts, Inc., had already recouped $360,000 of the negative cost by arranging the sale of worldwide television rights, thus increasing the chances for box-office profits in Spanish-speaking territories. A subtitled version of The Big Cube was also selected to play at the Acapulco Film Festival that same week.
       Var first-run box-office reports indicated that the film was initially released around 30 Apr 1969 in Cincinnati, OH, followed by openings throughout the month of May 1969 in Philadelphia, PA; Chicago, IL; Boston, MA; and Portland, OR. The Los Angeles, CA, engagement began 21 May 1969, while the New York City release did not occur until the following year, as revealed by a 28 Jan 1970 Var column reporting that showings had been added to several area theaters.
       According to an 18 Nov 1968 DV brief, Spanish language dubbing was provided by Producers Sound Services. The 11 May 1970 edition stated that both the original English print and the overdubbed version were screened for Mexican audiences.
       The 10 Mar 1969 DV review listed an “M” rating (as “Suggested for Mature Audiences”) from the Motion Picture Association of America (MPAA).