Isadora Wellington, known as Izzy, befriends Titania Moonsong, a wheelchair-bound old lady who lives at 13 Arnison Avenue. Rumour has it that Mrs Moonsong is a witch, which is hardly surprising: she has a black cat, Macbeth, her favourite piece of music is The Sorcerer's Apprentice and she makes peculiar concoctions from the herbs she grows in her garden. When Mrs Moonsong disappears and a strange hippy moves into her house, Izzy and her cousin, Joe, are concerned. It seems he is the one intent on casting spells and Mrs Moonsong is not the only one in danger.