A stray dog guards his lane every night, though no one ever asked him to. His bark breaks the silence, and he treats the whole street as his territory, keeping out strangers. By day he sleeps wherever he can and scavenges from bins to quiet his hunger. He is a poor animal, but he takes his duty seriously.
Then one midnight, suspicious strangers appear. He runs at them barking, but they win him over with a gentle touch and a feast better than any meal he has known. He eats gratefully and falls into the deepest sleep of his life. The poem then reveals that this sleep is permanent, and that the householder across from him has been killed. The food was apparently poisoned so the intruders could do their work.
The mood moves from quiet admiration to warmth and then to sorrow. The ending is the saddest part: police and neighbours attend to the dead man, while the faithful dog lies unnoticed nearby, with nobody to mourn him.