 Although RKO attempted to shoot second unit footage in South Korea, "One Minute to Zero" was filmed at Fort Carson, Colorado, using troops of the 148th Field Artillery.During a break, Mitchum, Egan, McGraw and other cast members showed up at a local hotel bar frequented by the soldiers in the nearby base.McGraw got into an argument with an army private escalating from a shoving match to a fistfight when Mitchum tried to break it up.