Mrs. Firkettle finds a small stone gargoyle, that has fallen off a lorry. She gifts it to her father, grandad Adam, to be put in his rockery instead of the gnome he wanted. Colin, Nan, Dave and Essie are asked by Reverend Sogood to help convert the old laundry into a village museum for the church. Colin is reading a diary about witches and burnings in the town, which occurred hundreds of years ago. A stranger appears and introduces himself as Twebele Alabaster, an African anthropologist, who is looking for a Grinnygog.