The Herdmans plus Halloween have always spelled disaster. Every year these six kids — the worst in the history of Woodrow Wilson School, and possibly even the world — wreak havoc on the whole town. They steal candy, spray-paint kids, and take anything that's not nailed down.
Now the mayor has had it. He's decided to cancel Halloween. There won't be any Herdmans to contend with this year, but there won't be any candy, either. And what's Halloween without candy? And without trick-or-treating? The Herdmans manage to turn the worst Halloween ever into the best Halloween ever in this uproarious sequel to The Best Christmas Pageant Ever.