With her father getting transferred and a sick mother being sent away to recover, Belinda's grandmother will be looking after her. An ordinary grandmother, just like any other grandmother, her mother claimed. But Belinda's grandmother is anything but ordinary! She's a witch with a very bossy, superior Siamese cat. Belinda's life suddenly becomes full of new friends and very unusual adventures.

Belinda is an only child and lonely. When her mother has to leave home to recover from an illness, her grandmother arrives to look after her. Belinda discovers to her delight that she has a very unusual grandmother. Her grandmother's cat, a superior Siamese called Senna, is equally unusual.

For the first time, Belinda's life is full of friends and adventures. She learns how to fly a moth-eaten carpet to visit her mother, turn a big black bear back into her father, and saves Senna from certain death.