 Many of the cast and crew struggled to contain their laughter in the aftermath of the shot; Butt himself stuffed a handkerchief into his mouth and left the room.Given the task of finding a suitable "Ridgemere Hall", production manager Janet Bone eventually settled on Clayesmore School, a boarding school in Iwerne Minster, Dorset.The school would not give permission for any of its floorboards to be pulled up, however, so the scene with Granddad undoing the fastening nut was filmed in a house belonging to Ray Butt's girlfriend.