The first eight seasons of the Walton are being relived through flashbacks.

Erin Walton is considering marrying her boyfriend Paul but her old boyfriend Ashley would like to get her back, Paul is not going to give her up so easily. Also Mary Ellen's boyfriend Jonesy is a veterinarian trying to establish a practice but nobody thinks he is competent.

Mary Ellen marries Jonesy but they don't exactly have a good start. While on their honeymoon, she suffers an accident that leaves her unable to bear children. She then shuts everyone, even Jonesy out. She then decides to go to the one person who could understand what she's going through, her mother, who is in Arizona recuperating.

Third Waltons reunion movie has most of the family split up on the days approaching Thanksgiving, c. 1946. But most of the family begins to arrive at Walton's Mountain beginning with John-Boy recovering from a case of writers block in New York followed by Jason now a struggling musician as well as John Walton who tries to get everyone together for the special event for Elizabeth, while newlyweds Erin and Paul plan to move out of the Walton homestead.

In the 1960s John-Boy is still living in New York, trying to persuade his fiancée to marry him. Elsewhere, Erin now has three children and is separated from Paul. Her decision to start seeing another man causes some indignation among the other Walton family members. Ike and Corabeth become grandparents when Aimee has a little baby daughter, while Elizabeth returns from Europe and reunites with Drew, her old beau.

It's 1964, John-Boy Walton is planning his wedding to Janet Gilchrist, the editor of a New York fashion magazine and the daughter of a diplomat. The two of them plan a small wedding and he invites the family and friends from Walton's Mountain to come to New York for the celebration. But Janet's Aunt Flo has other ideas and begins to take over their wedding preparations.

It's 1969 and John-Boy is the TV news anchor person in New York and is in the throes of writing a new book. He and a very pregnant Janet are making plans to return to Walton's Mountain for the celebration of John and Olivia's 40th wedding anniversary. Accompanying them is Aurora, a Time magazine photographer, who is doing a story on John-Boy.

John Boy and his family prepare for John Sr. homecoming to spend Christmas together, but after a storm comes in the way, John Boy has to find his father and the journey through it will change his life forever.

A remake of The Homecoming: A Christmas Story (1971).