Relates how the idea of jack-o-lanterns got started out in the prairies during a time when a mysterious stranger rewarded kind townsfolk and punished greedy politicians.
In their magic treehouse, Jack and Annie are again transported to King Arthur's realm, where invisible beings, giant ravens, and mistaken magic spells have a duke's castle in an uproar on Halloween night.
With Halloween approaching, Junie B. needs to find a costume that will scare off the real witches and ghosts that she believes will be out on the holiday.
Wobble is very unhappy because he keeps falling off his witch's new broomstick, but on Halloween, Maggie, his witch, finds something he can ride--the vacuum cleaner.