Professor Ellis Fowler teaches poetry at the Rock Spring School for Boys, as he has for the last 51 years. On the last day of class before Christmas, he goes over the works of Housman with his class and tries to impart some wisdom to them. Some are attentive, some bored. Fowler wishes them a Merry Christmas and proudly notes that they have all passed and gently comments that some may even have a future. Afterward, the Headmaster calls Fowler into his office and asks if he's seen the letter the trustees sent him. Fowler apologizes and assumes it's his yearly contract renewal, and promises that he will continue with the school through fair weather and foul. The Headmaster finally breaks it to him that Fowler is being retired on half-salary and a younger man will take his place. Shocked, Fowler walks out and as he wishes the boys good luck before going home, they note that he is crying.
That night, Fowler is listening to Handel's Messiah and refuses his housekeeper Miss Landers' offer of supper. He goes over photos of his old students, and their fathers who he also taught. Deciding that he has achieved nothing and never left a mark upon the world, Fowler takes a gun from his desk and goes outside. Miss Landers notices the gun is missing and runs to the door but Fowler has disappeared into the night.
Fowler goes to the school statue and prepares to shoot himself, but hears the class bells ringing. He goes to his classrom and before his astonished eyes all of his old students that have died appear at their desks. One of them, Artie Beechcraft, speaks of how he died at Iwo Jima but carried a book of poems that Fowler had taught in the class. The poems had inspired Beechcraft as he fought in the war. Another student, Butler, died of leukemia while performing experiments in radiation treatment for cancer, but speaks of how Fowler's teaching inspired him to put his life after those of others. The other students also speak of how Fowler helped make them the men that they were and thank him for his efforts. The class bells ring out again and the ghosts of Fowler's students disappear.
Late, Miss Landers calls the Headmaster to inform him that Fowler returned home, unharmed. Fowler is listening to the boys caroling outside. He sits down, happy and satisfied, and notes to Miss Landers that he is now ready to accept retirement and that he has indeed left his mark on the world.