A narrator accepts a posting to an isolated lighthouse after maritime service; the account follows enlistment formalities, the voyage to the station, and tense interactions with superiors and the island's lone keeper. Supply runs, weather, and cramped quarters shape daily life while an unexplained death and hints of past quarrels generate suspicion. Close attention to bureaucratic ritual and sensory details of the sea combine with the narrator's mounting apprehensions to create a claustrophobic atmosphere. The narrative examines solitude, duty, the corrosive effects of rumor and routine, and the gradual emergence of psychological unease in a remote maritime setting.