Ben and Amy Starbright stay with their grandmother while their parents go on a study field trip. The children find that Granny is not a typical granny when Granny's friend, Cornelia Starkstare, flies past their window on a broomstick.
Ben and Amy are in awe of Granny's magical abilities and are often surprised to encounter her many secrets and her intuition in various difficult situations. She has many strange and surprising ways to sort out problems that Amy and Ben encounter.
The world is very different for these children immersed in a world of magic.