Several people in Walnut Grove get very sick. A quarantine is set up in the church while the source of the illness is sought.
When it comes time to elect a new classroom president, Mary and Nellie are first to compete for the position. To even things out a bit, the boys strategically elect a shy, mentally delayed classmate named Elmer Dopkins. The trouble is, Elmer's overprotective father is fully aware of the boys' ulterior motives, but how far can a parent go to protect their bullied child?
During a trip to a teaching awards ceremony in Minneapolis, the stagecoach that Adam, Mary and a pregnant woman named Marge are riding in is involved in an accident. Mary is the only one who is able to free herself and is left to rely on her own wits to find help.
At the invitation of Eliza Jane, Laura attends a writing seminar in Arizona, but the experience is marred by a rude professor who cuts her down at every turn.
