Chimp Arthur's troubles with his Halloween costume make him look more of a chump than usual, to less purpose: the dialogues with ever-helpful little sister Violet are mechanical, the outcome the result of chance happenings. Planning to go to the school party as a ghost, Arthur is disappointed to learn there'll be other ghosts: ""Now no one will be scared."" Then he has yearnings to be ""an original""--as Violet's friend Wilma says of her little cousin Peter, gotten up as a big chocolate kiss. Then he just wants to find his homework, or he can't go to the party at all. And in the course of searching for it in the garbage, Arthur acquires so many odd accoutrements--including an old-rug wig that smells of tuna fish and attracts cats--that he's hailed as the Spirit of Halloween, and takes the originality prize. Hectic but slack.