The Case of the Magic Christmas Bell — Francine Pascal

Jessica and Elizabeth Wakefield and their friends in the Snoopers Club have uncovered their most difficult case yet! The bell that helps Santa's reindeer fly has fallen off the sleigh: If the Snoopers don't find it, Santa won't be able to deliver any presents this Christmas. They have to work fast, though, because a bad elf named Fritzi is looking for the bell, too. Will the Snoopers be able to save Christmas?