“Brokeback Mountain” begins in the present with Ennis Del Mar waking up in his trailer parked on the Wyoming ranch where he has been working. He thinks about finding a new job since the owner is ready to sell the ranch and acknowledges that he may have to live with his daughter for a while. This morning, though, he feels happy because he dreamed of Jack Twist the night before and of their time together on Brokeback Mountain.
At this point, the narrative shifts to 1983, when he and Jack were both teenagers during Ennis’s first summer on the mountain where they worked as sheep herders. Day after day, Ennis tends the camp while Jack herds the sheep and sleeps out on the mountain with them. One day, when Jack complains about his “commutin four hours a day,” he accepts Ennis’s offer to switch jobs.
Every evening, they share supper by the campfire, “talking horses and rodeo, roughstock events, wrecks and injuries sustained,” and other details of their hard lives in the West. Toward the end of the summer when they shift the camp, the distance Ennis has to ride out to the sheep grows longer and he begins to stay later at the camp at night. One evening, after the two sing drunken songs by the campfire, Ennis decides it is too late to go out to the sheep and so beds down at the campsite. After his shivering wakes Jack, the latter insists that Ennis share his bedroll. Soon after, the two have sex, something Ennis had never done before.
Their sexual activity becomes more frequent in the following days while they both insist that neither of them is “queer.” One day the foreman, Joe Aguirre, watches them together through his binoculars. Toward the end of the summer, after Ennis spends an entire night with Jack, the sheep wander off and mix with another group of sheep. Ennis tries unsuccessfully to sort them out. When they come down off the mountain after the first snowfall, Aguirre notes with displeasure that the sheep count is low and the herd is mixed.
When Jack asks Ennis if he is coming back to the mountain the next summer, Ennis tells him that he will be getting married in December and then will try to find work on a ranch. Jack determines to go back home and then maybe to Texas, and the two say an awkward goodbye. As Ennis drives away, his gut wrenches and he retches along the side of the road. He feels “about as bad as he ever had,” a feeling that stays with him for a long time.