Marie Belloc Lowndes, the brother of Hilare Belloc, had a prolific writing career that spanned more than forty years, producing an average of one work a year. Most of her books are now out of print, but this, her most popular novel, is still widely available. It is loosely based on the Jack the Ripper murders and has been filmed several times, notably by Alfred Hitchcock in 1927.
The story centres on a lodging house in London run by Mr. and Mrs. Bunting. They are in desperate circumstances, without boarders, when one foggy evening (this is London remember) a mysterious stranger, the ironically named Mr. Sleuth, arrives and rents rooms. He acts very oddly, staying in his room all day, mainly reading the Bible, and he leaves the house only after dark. At the same time, a series of brutal murders of young women takes place, and Mrs. Bunting becomes worried by the coincidence of the timings of murders and Mr. Sleuth's nocturnal wanderings, and the fact that he keeps his bag locked in a cupboard in his room. But she does nothing, because he is clearly very distressed and she feels sorry for him. She also knows that if he were to leave their previous desperate financial state would return.
Mr. Bunting's daughter from a former marriage, Daisy, arrives for a short visit and this prompts frequent visits by Chandler, a young friend of the Buntings and Daisy's would-be boy friend. He is a policeman, and one morning tells the Buntings about another murder that had been committed the night before. Mr. Bunting is shaken, because he had found blood on his hand after brushing against Mr. Sleuth's coat that same evening, when they had met coming home. Both the Buntings are now worried.
The climax comes when Mr. Sleuth takes Mrs. Bunting and Daisy to Madame Tussaud's, where by chance they see a party being shown round by the new Chief of Police, Sir John Burney. Mr. Sleuth is incensed and threatens to murder Mrs. Bunting, because we learn that Sir John was responsible for having Mr. Sleuth confined as a madman who had murdered before. Mr. Sleuth thinks Mrs. Bunting has betrayed him. He flees the exhibition, but when Mrs. Bunting and Daisy return home he has gone and never returns. Like the Jack the Ripper case, the murders cease.
This is a very good read. Although we quickly realize that Mr. Sleuth is the killer, and there are a few unlikely coincidences that are essential for the plot, the story still holds ones attention. The writing is uncomplicated, the small cast of characters is very believable, and the tension is well maintained right to the end.