In the novel N or M?, Mrs Calfont is a English woman who works in refugee relief. She testified at the inquest into the death of the Polish refugee Vanda Polonska.
Mrs Calfont had worked with Polonska and she formally identified the body. She told the coroner that Polonska had come to England with a cousin and her husband. These two were her only relatives as far as she knew. Mrs Calfont believed that Polonska had been through severe hardship in Poland (presumably as a result of the German conquest). Many members of her family including children had been killed. Mrs Calfont also observed that Polonska was "slightly mental". She was not at all grateful for anything done for her, she muttered to herself a lot and did not communicate much. A domestic post had been found for her, but she had left it without notice some weeks ago and without reporting to the police.
Mrs Calfont is described as "a thin-lipped, gimlet-eyed woman". Her testimony served to reinforce the suspicion that Polonska might be a fifth columnist.