Beth Bradley’s younger brother Charlie is outraged that Halloween has been canceled this year. Though Charlie thinks this is the worst thing that could have happened, the next morning has something far worse in store.

Beth’s mother blames the Herdmans for the change in the town’s Halloween traditions. The Herdmans are a family of six children—Ralph, Imogene, Leroy, Claude, Ollie, and Gladys—who live with their mother and their one-eyed cat in a house at the bottom of Sproul Hill. The Herdman siblings are notorious for causing trouble. They once put their cat in the washing machine, robbing it of whatever good nature it ever had. Beth notes that the neighbors would have complained about the Herdmans, except that all their neighbors moved away to avoid the mayhem. Even Mrs. Herdman prefers to stay at work instead of spending time with her children. Just this year, the Herdmans have stolen the flag on Flag Day, ruined school bake sales, and replaced the kindergarten’s pet mice with guinea pigs. However, the worst thing they did in recent memory was to stick eight children, including Charlie, into the revolving door at the bank. The door wouldn’t budge, the children couldn’t get out, and the fire department had to be called.