Book is in French Mary Anne should never have thrown away the letter she received in the mail. Since that day, the members of the Baby-Sitters Club have experienced a series of mishaps. As Halloween approaches, Mary Anne is even more worried: who knows what other misfortune awaits them? Then she finds a new message in her mailbox: Wear this evil necklace, otherwise... Mary Anne must follow these instructions, but who sent this necklace? And why to her? The Baby-Sitters Club will never emerge from this period of bad luck if its members fail to solve this mystery!