In the novel The Seven Dials Mystery, Dr Cassell is a doctor with a practice in one of the towns on the road between Chimneys and London. While "Bundle" was driving to London, a man suddenly sprang into the road in front of her. "Bundle" swerved but the man fell and she thought she had hit him and killed him. She lifted him into her car and drove him to Dr Cassell's clinic. There, Cassell told her that she did not in fact hit him. The man, identified as Ronny Devereux, had died from a gunshot wound.