Janet West and Laura Stebbing operated the mobile library that traveled the villages of north-east Essex. When Janet's body was found at a lonely spot on the river bank, Chief Inspector Millson wondered why anyone would murder such a respectable and well-liked woman. There was no obvious suspect and as his investigation proceeded he discovered there was more to the friendly librarian than he realized. When Laura took part in a reconstruction of Janet's movements on the night she was killed, there were suddenly three suspects. In the end there were three murders, too...