It is 1905, and a young doctor just out of internship in Chicago has decided to head for the southwest to seek his fortune. He finds himself on a slow train in southern New Mexico, sitting across from a Sister of Mercy "in her black robes, skirts and sleeves, and heavy starch." When the train stops, the doctor inquires about a group of men huddled on the platform. They surround a severely ill Mexican worker, who turns out to have appendicitis. The doctor insists that only an immediate operation will save his life, but the Mexicans are violently opposed to surgery. Eventually, the doctor enlists the nun’s help to persuade them.
In the blistering heat, they carry the man to a shed where the doctor performs an appendectomy with instruments in his black bag, including morphine and chloroform. For the next 24 hours, he and the nun watch over the man, and then carry him to the nearest town on the next train. He survives, which is good because otherwise the Mexicans have threatened to kill the doctor. The nun, who throughout has been cool toward the doctor because of his use of "rough" language, proceeds on her way to Texas.
