Eleven-year-old Melanie persuades her brother, Cory, and their little sister, Erin to go to a magic show. Arthur, their pesky neighbor, joins them, a recipe for disaster. They encounter Mrs. Seraphina, who claims she can grant wishes. Erin mentions all the magic The Great Mondo will do at the show. Cory says, "I wish he could...." The four children are soon running from Mondo, after he is fired for creating a stampede of rabbits and making the theater manager really float. At Daisy's Do-nuts, they worry how to undo the wish. When Mrs. Seraphina shows up, one wish leads to another. Mondo ends up driving a cab. Daisy's Do-nuts is on the evening news. Melanie is sick of wishes. She has other worries--the new boy in sixth grade; her parents' divorce; the fact that Mondo is giving her mother rides home from work. Ultimately Melanie learns the difference between "cool" and reality, tricks and magic, and what makes a real family.