It is Thanksgiving and Lisa assembles a decorative centerpiece for the dinner table. The Simpson family sits down to give thanks along with Grampa, Patty, Selma, and Mrs. Bouvier. When Lisa places the centerpiece on the table, she argues with Bart about where it should go since there is no room left for the turkey. In the ensuing fight, Bart accidentally throws the centerpiece into the fireplace and it burns up. Devastated, Lisa runs to her room crying, while Bart is sent to his room by his parents for the incident.
Convinced he has not done anything wrong, Bart decides to run away from home, taking Santa's Little Helper with him. Walking the streets alone, he visits a breadline that is serving Thanksgiving dinner for homeless people. A television crew led by Kent Brockman is covering the event, and they interview Bart on live television. The family sees the report and calls the police. Homer and Marge start to regret the bad things they said to Bart, who eventually returns home feeling remorseful. However, the situation is worsened when he imagines his family blaming him for everything if he apologized for "ruining" Thanksgiving. Back to the present, he realizes that it was all his own imagination. He climbs up onto the roof of the house to think things out. Hearing Lisa cry because she misses him, Bart calls for her to come onto the roof. He realizes that what he did was wrong and apologizes to her and she accepts and kisses him. Bart rejoins the family to enjoy a meal of Thanksgiving leftovers later.