Three very different 11-year-old girls live on Gumm Street: Franny thrives on adventure, Cat is athletic with ESP, and Pru is safety conscious and loves to have her nose in a book. Around the time that a fourth girl, Ivy, moves to Gumm Street, strange things start to happen. The piano teacher and friend of the girls, Mr. Staccato, floats away into the sky, a slipper from
The Wizard of Oz disappears, and a woman named Cha-Cha Staccato arrives bearing an uncanny resemblance to a certain wicked witch.
The girls must overcome their differences and work as a team to get to the bottom of these mysterious happenings, save themselves from being squeezed into a potion, and even save their beloved town of Sherbet.