Grace Bradley and the Bradley Family (daughter Beth, son Charlie, and husband/father Bob Bradley) had to take over their church's annual Christmas pageant after the original play director (Mrs. Armstrong) broke her leg. To make matters worse, Charlie Bradley told Leroy Herdman, one of six horrible Herdman kids (Imogene, Ralph, Leroy, Ollie, Claude, and Gladys), that people who go to Sunday School get free refreshments, to make him feel dumb about stealing his dessert. This makes the Herdmans infiltrate the only safe haven in all of town.
The next Sunday during Sunday school, Imogene had heard about the pageant and asked know-it-all Alice Wendleken (best friend of Beth Bradley) what a pageant was. Imogene was interested in this "Christmas Pageant" and decided to sign all the Herdmans up. This could only mean one thing;TROUBLE!