Next to Christmas, no holiday inspires more “special episodes” than Halloween. I guess this makes some kind of sense. It’s like a day off for gag writers. Halloween episodes give characters an excuse to dress up in silly costumes and act frightened, two activities that don’t require original thought or writing.

Tonight’s most ambitious Halloween-themed show has to be “Life with Bonnie” (8:30 p.m., ABC). Everyone who works on Bonnie’s fictional show, “Morning Chicago,” dresses up as characters from “The Wizard of Oz” and, as the episode progresses, they get a little more into character than planned. Carl Reiner guest stars as the Wizard-like station owner, whose image appears via video monitor and sends shivers through the cast and crew.

Other Halloween themed sitcoms include “George Lopez” (7 p.m., ABC), in which George and his co-workers sponsor a charity haunted house. Ghosts abound on “Reba” (7 p.m., WB), and Faith falls for a hunk in a costume on “Hope & Faith” (8 p.m., ABC).

Tonight’s other highlights

â Raven and Chelsea are pointedly not invited to a costume party on “That’s So Raven” (6 p.m., Disney)

â Premiere of the feature-length cartoon “Scooby-Doo and the Legend of the Vampire” (7 p.m., Cartoon Network).

â A divine request to join the pep squad on “Joan of Arcadia” (7 p.m., CBS).

â Scheduled on a two-hour “Dateline” (7 p.m., NBC): a man stands trial for the brutal murder of his wife and children.