O'Brien begins this vignette typically, at the end of the story. We know that Rat Kiley gets "hurt," but we do not know how badly and the nature of the wound. The story then moves almost nowhere as we know how it will end before it begins. Like so many of O'Brien's vignette, the point is not what happens as much as why it happens.
"Night Life" is about the precarious balance that a soldier keeps. In this case, what upsets the balance is a change in routine. It does not matter exactly what the routine is, just that something has changed. Despite the joke that they were all living the night life, the switch from days to nights made it a tense time for everyone. The tension simply overtakes Rat more than the others, but they all feel it. O'Brien shows us how unstable they all were, and by what a thin thread they were holding onto their control, whatever control they had.
Within the change is the element of night, itself a terrifying concept. O'Brien delivers a vivid account of the complete darkness of night in Vietnam and how it affects the company. The inability to blink or see any light for hours and hours, day after day, bears down on the troops, and for whatever reason (again, the element of randomness indicating that none of them were safer than any other), even more heavily on Rat Kiley.
