In the novel N or M?, Arthur Sprot is the husband of Mrs Sprot, and the father of Betty Sprot.
Mr Sprot is described as having a "sheeplike and somewhat unattractive face". According to Mrs O'Rourke, he is a clerk in an insurance office, and has had his wife and child at Sans Souci since the beginning of the war because he is terrified of air raids. He is described as being an "amiable but not very interesting young man".
After the death of Vanda Polonska, Mr Sprot is "hysterically summoned by telegraph", and rushes down to see his wife. However, he has to return to the city the same day.