Are you kidding?
Zachary Scott's daughter is going thru his suitcase and finds some interesting items. They are war souvenirs given to him by his old sergeant, for whom he just designed a building. Among the items is a Nazi flag, armband, hat and pistol. His daughter picks up the pistol and asks if she can have it. He says no, it is not a toy and puts it away. Later that night, he accidentally comes across the pistol during an argument with his wife. This pistol is used to shoot the wife.
So this pistol came over from Europe, was given to Zachary Scott who brought it home from a trip (car, plane, train?), and all the time it was loaded!!!!