One June evening, nine-year-old Sylvia is searching for her cow, Mistress Moolly, in the woods. As usual, it takes a while to find Mistress Moolly because the cow enjoys hiding. Mistress Moolly has learned that if she stands perfectly still her large bell will not make noise. Sylvia enjoys the ritual and doesn’t mind indulging Mistress Moolly’s mischief because she has a good milk supply and Sylvia doesn’t have any children to play with. She compares the ritual to a game of hide and seek. After Sylvia finds her, Mistress Moolly begins to lead them home. Because they are later than usual Sylvia worries what her grandmother will say. However, her grandmother is familiar with the cow’s behavior, and Sylvia knows she will forgive her for taking a long time.

Sylvia’s grandmother, Mrs. Tilley, waits for them at home. She notices it’s late, but she isn’t upset. She thinks that Sylvia dawdles on purpose because she loves being outdoors. Mrs. Tilley brought Sylvia home to live with her after a visit to her daughter in the city a year earlier. Sylvia’s parents have a lot of children, but Mrs. Tilley chooses Sylvia because she is afraid of people and people are scarce in the countryside. When they arrive at Mrs. Tilley’s farm, a cat greets Sylvia at the door. She announces that the place is so beautiful, she never wants to return home.

Back in the forest, Sylvia admires the nature around her. She cools her feet in the water when Mistress Moolly stops for a drink. She feels peaceful and sleepy as she listens to the birds singing their evening songs. Evening sets in and it becomes darker. Sylvia remembers a boy in the city who used to bully her. She feels afraid and begins to walk faster. Suddenly, Sylvia hears a loud, unnatural whistle. Frightened, she leaves Mistress Moolly and hides in the bushes. However, she is not quick enough and the man who whistled spots her. He yells out a question about the nearest road. Sylvia is afraid and can barely speak to or look at the man. She notices that he is carrying a gun. He begins to walk next to Sylvia and explains in a friendly voice that he is a lost hunter and wonders whether he can stay at her house for the night because it is so late. Sylvia worries that Mrs. Tilley will be angry when she arrives home with a stranger.
When they arrive at the house, Mrs. Tilley listens to the hunter’s story and graciously welcomes him to stay the night. Sylvia is still afraid of him and is a little surprised by Mrs. Tilley’s reaction. 
 The story changes to the hunter’s point of view. He is surprised and pleased to find Mrs. Tilley’s home to be clean and comfortable. His opinion is that homes in the New England wilderness tend to be dirty and uncomfortable. He is overly friendly to Mrs. Tilley and Sylvia. He watches Sylvia closely, listens to Mrs. Tilley reminisce, and compliments her food. After the meal, the three of them sit on the porch talking. In a thick dialect, Mrs. Tilley speaks fondly of Sylvia and talks nostalgically about her children. Four passed away, and only Sylvia’s mother and one son are still alive. The son, Dan, moved to California, although she is worried he is also dead because he hasn’t contacted her in a while. She boasts about Dan’s hunting talent. She understands why he left because she would have traveled if she could have.

Mrs. Tilley explains that Sylvia is a lot like Dan because she knows the woods well and she likes to befriend birds. The information about Sylvia befriending birds intrigues the hunter. He interrupts Mrs. Tilley's sad reflections on her son to explain that he has been collecting birds since he was a boy. He kills and stuffs them to keep in his home. He proudly explains that he has personally killed every bird in his collection. He is currently searching for a few rare birds, one of which is a white heron. He spotted it a few days prior and followed the bird. The hunter looks to Sylvia to see if she recognizes the description. He explains that the heron’s nest would be up in a very high tree like a hawk’s nest. He says he would pay ten dollars to anyone who helps him locate the rare bird, which is a lot of money for Mrs. Tilly and Sylvia. Sylvia watches a toad to avoid the hunter’s eyes, but she realizes she has seen the white heron. That night, Mrs. Tilly and Sylvia both dream about what they could buy with ten dollars.

The next day, Sylvia and the hunter head out into the woods together to find the heron. Sylvia is no longer afraid of him. She begins to develop a small crush as he shares his knowledge of birds and gives her a jack-knife. While she admires the hunter and finds him charming, she does not understand why he kills the birds he proclaims to love. Sylvia stays quiet, following the hunter's lead, even though she knows the woods well. She is disappointed they don’t find the heron, but she does not volunteer that she has seen it before. They do locate Mistress Moolly and head home. When they pass the place where Sylvia first heard the Hunter whistle, Sylvia smiles.

Sylvia knows of a great pine tree nearby that was presumably left behind by loggers long ago. The pine is much taller than all the trees surrounding it and Sylvia’s sure if she climbs up high enough, she could locate the heron’s nest. Sylvia stays up most of the night excitedly thinking about climbing the pine and she leaves home before dawn. The climb is difficult and dangerous, but she is determined to find the nest. The sun begins to rise as Sylvia reaches the top of the pine. She is awestruck by the panoramic view before her. She takes in the beauty of the countryside, the birds singing and flying below, and the distant ships out at sea. Then, she sees the heron. Sylvia stays very still as the heron lands on a nearby branch and calls out to its mate. Soon, some noisy cat-birds disturb the majestic heron and it flies off. Sylvia watches as the heron soars across the sun and lands in its nest. Excited about telling the hunter that she has located the nest, Sylvia climbs down and heads home. She wonders how he will react.

At home, Mrs. Tilley notices Sylvia’s bed is empty and calls out for her. The hunter awakens and begins to dress for another day of hunting. As he dresses, the hunter thinks about Sylvia's behavior. He is sure that she has seen the heron and is determined to get the information from her. He sees her approaching the farm and notices her already shabby clothes are torn and stained. The hunter and Mrs. Tilley question Sylvia, but she finds herself unable to speak. She thinks of the charming hunter’s money and her grandmother’s disappointment, but she cannot let the hunter kill the heron. For years after, Sylvia often recalls the hunter’s whistle and wonders if she made the right choice. She forgets how sad she felt when he shot and killed birds and wonders if he would have made a better companion than the birds she chose. The story closes with the narrator imploring the natural world to comfort Sylvia because the beauty of nature can be a great solace.