In summer 1960, Pathé Laboratories announced The Deadly Companions as one of twelve upcoming pictures on its new production-distribution slate with Alpha Distributing Corp., the 29 Aug 1960 DV reported. Maureen O'Hara was cast in the leading role, and her brother, Charles B. Fitzsimons, was set to produce, as stated in a 15 Sep 1960 DV brief. According to a 9 Nov 1960 Var article, the project, budgeted at over $1 million, was slated to be the first to go into production for the newly formed Pathé-Alpha Distributing Co. Co-financing was said to be provided by Motion Picture Investors (MPI), an "exhibitor-backed investment trust," as indicated in a 25 Jan 1961 Var item. MPI, which had been formed in 1958 "to enable theatreowners to acquire stock in the film companies so that exhibitors could have a voice in policy-making," had not previously been involved in motion picture production.
       Shooting was scheduled to begin in late Dec 1960 or early Jan 1961, for a planned release in Apr or May 1961. The 18 Jan 1961 DV indicated that Universal International would handle the U.S. release, although the studio received no further mention in contemporary sources. On 23 Dec 1960, a DV news brief noted that Pathé-Alpha had recently decided to film in Pathé Color instead of black-and-white, and to increase the budget to $1.5 million. Conflicting figures for the budget were later cited in a 29 Aug 1962 Var article, which claimed the film was "brought in for $390,000," and had been partly financed by the Walter Reade Organization, which had contributed $150,000 but was repaid $60,000 when the film was completed under budget. Walter Reade, Jr. was the head of MPI, as noted in the 12 Dec 1962 Var, which indicated that MPI, not the Walter Reade Organization, had contributed the $150,000.
       Principal photography began in Tucson, AZ, on 17 Jan 1961, as stated in a 27 Jan 1961 DV production chart. While filming was underway, an item in the 2 Feb 1961 DV announced that singer Pepe Callahan had been cast in a role, and Callahan's friend, Julio Carona, had been signed to score the picture.
       The world premiere was scheduled for 6 Jun 1961 in Tucson, as noted in a 21 Apr 1961 DV brief. According to the 14 Apr 1961 DV, 400 prints were ordered for "June-July saturation bookings," and the 7 Jun 1961 DV reported that 871 playdates had been guaranteed by exhibitors. A 7 Jun 1961 opening was planned in Los Angeles, CA, where the picture was set to be screened on a double bill with Operation Eichmann (1961, see entry). The following year, a 5 Dec 1962 DV brief referred to The Deadly Companions as a box-office "dud," and noted that it would be reissued by Mercury Films in Jan 1963 under the new title Trigger Happy. Since its initial release, the picture's commercial failure had reportedly caused MPI's net assets to drop from $337,870 to $45,971.
       In fall 1961, Pathé-Alpha, its parent company, America Corp., and others were sued for "breach of contract and accounting, fraud and conspiracy" by Advertising Engineers Corp., a Los Angeles-based advertising company, the 20 Sep 1961 DV reported. Advertising Engineers Corp. alleged that Pathé-Alpha had withheld payment for advertising and marketing services rendered, for which it had promised to pay five percent of the film's gross receipts. The plaintiff sought $1.2 million in damages.
       Sam Peckinpah, who had established himself as a television director, made his feature film directing debut with The Deadly Companions. Despite the film's lack of box-office success, a review in the 6 Jun 1961 DV called it "an auspicious debut," and the 14 Jun 1961 LAT stated, "Peckinpah has made a distinct impression with 'The Deadly Companions,' a western that is offbeat and strange but that reveals an approach as original as George Stevens' in 'Shane.'"